AIRPORT PAVEMENT INSPECTION by PCI William H. Green, P.E. and -,Roy A. Eckrose, P.E. 
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 
, } AIRPORT PAVEMENT INSPECTION by P C I William H. Green, P.E. and Roy A. Eckrose, P.E. SECOND EDITION published by ECKROSE/GREEN ASSOCIATES Madison, Wisconsin Copyright 1988 A portion
of the text in this manual has been reproduced from Federal Aviation Administration Advisory Circular 150/5380-6, titled "Guidelines and Procedures for Maintenance of Airports". That
text is underlined and identified as a reproduction, and is not protected. All other material is copyright protected and all rights are reserved. No part of this publication may be reproduced
in any form, or used to establish standards for PCI inspection, or as a reference for conducting PCI inspection, without the written permission of the authors. Cover design by Nautilus
Printing & Publishing Co., Inc. Madison, Wisconsin 
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PREFACE CHAPTER 1 CHAPTER 2 CHAPTER 3 CHAPTER 4 CHAPTER 5 CHAPTER 6 Appendix A APpendix B TABLE OF CONTENTS Pavement Management Pavement Evaluation and Management Systems Site Layout
and Inspection Pavement Characteristics Distress Identification and Measurement Drainage Condition Index Procedures Feature Data Summary Sample unit Data Sheets 
PREFACE The Pavement Condition Index (PCI) method of documenting pavement conditions was developed by the United States Army Corps of Engineers in the decade of the 1970s. It may prove
to be the most revolutionary breakthrough in Civil Engineering technology in this century. The PCI inspection and evaluation technique makes possible, for the first time, an objective
assessment of pavement condition based on visual examination. The concept is based on easily recognized distress types, each influencing the condition index according to an emphirical
standard developed from collective judgements of a large group of experienced pavement engineers. The real value of PCI, as a pavement management tool, is that the condition of a pavement
section can be confirmed, within reasonable limits of accuracy, by any qualified pavement inspector. With this confidence in reported data, engineers can predict deterioration rates,
forecast serviceability, program maintenance and improvement actions, and estimate costs with accuracy never before possible. Because rating results are objective (repeatable), evaluation
of pavement dynamics over time is made possible by comparing condition ratings from subsequent years during the life of the pavement. This can lead to an ever improving knowledge of
a pavement's "personality" with a corresponding increase in ability to accurately program maintenance and improvements. The PCI method of condition rating is extremely important to persons
responsible for management of pavement systems. It is a giant step forward in Civil Engineering technology at a time when preservation of pavement systems is more crucial than ever before.
However, PCI is a new technology, being implemented for the first time by most users. As with nearly all new technologies, there is room for improvement. PCI procedures need to be refined,
from time to time, by persons who have used them extensively, and have tested and examined them in detail. This manual is such a refinement. The intent and purpose of initial pcr standardization
is retained in every sense. PCI standards have been strengthened and 
refined to improve consistency of data collection and to provide guidance to users in preparing for and conducting inspections. By use of this manual, repeatability and quality assurance
can be increased substantially. Minimum standards established herein have never before been achievable using PCI inspection procedures. This manual has been developed for use by inspectors
trained in PCI inspection techniques by Eckrose/Green Associates. It presents the collective judgements, interpretations and techniques of the authors, and inspectors working under supervision
of the authors, in five years of extensive field inspections on more than 275 airports. With proper training and supervision, any maintenance technician, pavement designer, construction
supervisor, or surveyor can expect to achieve standards established by this manual. This SECOND EDITION of "Airport Pavement Inspection by PCI" has significant improvements over the
initial publication. There are more than 200 photographs in this edition to support the text. A picture, in distress identification, is worth at least 1000 words, and these photographs
represent a veritable library of value. We have further refined many of our "Additional Criteria" in response to questions and requests from our field crews. Chapter 2 has been revised
to provide a direct comparison of the MicroPAVER computer program with Eckrose/Green's AIRPAV software. We have expanded Chapter 3, "Site Layout Procedures", to further amplify our records
research and pavement layout techniques. And, we have added Chapter 6, "Drainage Condition Index Procedures", to introduce a new developing for evaluation of drassociated with pavement.
technology we are ainage conditions It is a rare privilege to work in a field which is evolving as rapidly as pavement management is today. Each day presents exciting new challenges,
and there are countless opportunities for innovation and improvement. But there is a special responsibility, also. In this emerging technology, with few established standards and virtually
no traditions, one must be especially careful not to "oversell" a concept, or to mislead the using public. We believe this manual is a responsible contribution to pavement management
technology. The Authors 
____________ 􀁾_______ 􀁾_____􀁾__􀁾􀁟􀁾__ N _____ 􀁾______ N __􀁾__________________ 􀁾􀁟Airport Pavement Inspection by PCI CHAPTER I PAVEMENT MANAGEMENT BACKGROUND Pavement is nearly
as important to our way of life as are food and shelter. Next to assuring the means to sustain life, mobility is, perhaps, the most fundamental essential of our society. To enhance mobility,
we have developed vehicles to transport us on land and water and in the air. Ground transportation, as we know it, would not be possible without our vast networks of paved streets and
highways. Air transportation, as well, requires paved airports at origin and destination points. A pavement system reflects the needs of society for mobility. Large population centers
are supported by complex pavement systems. Small town and rural areas have more simple needs, and supporting pavement systems) reflect those needs. Pavement has but one purpose -to support
and provide a smooth all weather surface for wheeled vehicles. Pavement composition is dictated by many factors. Kinds and volumes of traffic are primary. Terrain, climate and soil conditions
are also important. Other factors include political and engineering preference, availability of raw materials and construction expertise. POLITICAL FACTOR In any pavement system, political
leaders are most concerned about safety, service and appearance. The system must serve society. It must provide access where people want to go, with safety, and in harmony with its environment.
When a pavement system fails in any of these areas, responsible elected and appointed officials get complaints from their constituents. 1-1 
􀁟􀁾____N __􀁾___________􀁾_____ N _______________________􀁾􀁟Airport Pavement Inspection by PCI PLANNING FACTOR The ability of a pavement system to serve society is largely a function
of planning. Before any pavement system, or system expansion, can be built it must be integrated conceptually with other expectations and demands of the people. Planners dictate the
character of a pavement system by identifying existing needs and forecasting future needs. Planning provides a transition between political and engineering concerns. Planners anticipate
and respond to the needs of society by conceptualizing the evolving pavement system within constraints of financing, environment, politics and engineering. ENGINEERING FACTOR Engineers
design pavement to be safe, serviceable, economical, durable and attractive. Their concerns are of drainage and materials. They establish load and volume capacity, pavement type. composition
and thickness. They build, maintain and rehabilitate the pavement system for as long as it is is needed by society. CONTROLLING FACTOR Funding is the means by which society achieves
the support systems it demands. Society pays taxes to finance water and sewer systems, parks, schools. streets and highways and airports. Some taxes are dedicated, but most are entrusted
to elected representatives. These political leaders must then apportion funds among all the support systems in place. The process keeps the systems in balance and assures efficient evolution
of our quality of life. CATALYSTS Society is made up of special interest groups who compete for available tax dollars. These groups provide political leaders with awareness of need,
potential benefits and consequences to society associated with funding of individual support systems. Their contribution is invaluable in making tax apportionments. 1-2 
􀁾􀁾􀁾􀁎􀁟􀁎􀀠,, ____________ 􀁾___________________________________________ 􀁾􀁾􀀠Airport Pavement Inspection by PCI This competition for public funds is the foundation upon which our
support systems are built. It provides checks and balances to assure that funds will be used where they are most needed. It encourages public awareness and participation. It requires
each special interest group to critically examine and justify its needs. Since credibility is so very important, it demands competent use of allocated funds and proof thereof. It requires
management. MANAGING THE PAVEMENT SYSTEM Responsibilities. A manager's first responsibility is to make best possible use of public funds entrusted to him. He must expand the pavement
system, as authorized, to serve society's needs. He also must maintain the system in safe and serviceable condition. When there are not enough funds provided to do all the things that
are needed, he must decide Which needs are most important. And he must document his needs and support his decisions to justify future funding. Fulfilling these responsibilities is what
pavement management is all about. Overview. The first step in pavement management is to determine what the needs are. This is done by critically examining all pavement in the system.
This will require at least a comprehensive visual inspection and analysis of the importance of various pavement sections to the function of the system. Ultimately, priorities will be
established based on pavement condition, function and available resources. Once priorities are set, it is important to decide the best way to deal with the pavement and what it will
cost. It is then necessary to finance the work. When the work starts it is important to supervise to insure full value for the investment. Finally, activities must be documented to measure
progress, improve techniques, and ensure program continuity. In summary, pavement management requires regular inspections, periodic reevaluation of priorities, deciding among action
alternatives, a continuing campaign for financial support, supervision of project ______ 􀁾􀀠) 1-3 
􀁾􀀠􀁾􀀠􀁾__ N __________ _____ ______NN __________ ________________________________Airport Pavement Inspection by PCI activities, and documentation of results. Inventory. Visual inspection
is a very good evaluation technique. It is simple and inexpensive and provides a great deal of valuable information about pavement conditions. However, it is often wise to make additional
tests to identify conditions not definable by visual inspection. The most traditional method is to obtain samples for laboratory testing. Advantages are that actual materials can be
examined and tested. Disadvantages are that a piece of pavement is destroyed in taking the sample, costs can be quite high, and results represent only conditions at the spot of the sample.
In recent years several alternative testing techniques have been developed, many of which are nondestructive in nature and allow examination of considerably broader expanses of pavement
than is practical with physical sampling. Among nondestructive testing techniques are nuclear meters, electronic devices, radar units, impact and dynamic loading devices, and friction
measuring equipment. Each can provide valuable information of conditions and each has certain limitations. In practice, it is appropriate to select from nondestructive techniques to
fulfill specific investigative requirements. Priorities. In order to establish functional priorities, pavement should be divided into sections in such a way that each section represents
a single operational function. Within functional areas, pavements should be further subdivided into areas of like construction. All pavement in a system should be included. Priorities
should be based on operational importance to the system, use demand, rate of deterioration and condition. Assigning of priorities and allocating of funds should always be done in the
interest of achieving a more balanced pavement system. The objective must be to maintain well defined minimum service levels throughout the system. Evaluations. If identifying problems
was all a manager had to do, management would be easy. The real challenge is to formulate solutions and orchestrate them to successful completion. Formulating solutions in pavement :
./1-4 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭management
requires analyzing pavement conditions, defining alternative corrective actions and assessing the consequences of those actions. Credible alternative actions will vary with the function
of a pavement section and its condition. Finding the best solutions to pavement problems is very important. It deserves professional input, and the credibility of any program may well
depend upon the manager's ability to justify his approach to this process. Financing. Before any preservation or expansion can take place, it is necessary to obtain funding for the work.
Selling the program on its merits to public officials is an ongoing management responsibility. Pavement management tools can provide a tremendous advantage in the competition for public
funds. They provide hard evidence of the condition of pavement in the system and the benefits benefits to be expected. By comparing remaining service life projections of a "do nothing"
option with service life projections of recommended solutions, it is possible to predict consequences of any failure to finance the program. Implementation. With the budget approved
and the money available, what more can be expected of a manager? The answer to this question is simple. Fulfilling those expectations is not. It is a manager's responsibility to use
public funds in the most effective manner possible. This reqUires preparing precise instructions for the use of those funds and supervising the work in progress value received is equal
to value given. professional assistance is almost always of action. to Ha insure that ere, again, wise course Documentation. It is important to keep accurate records of accomplishments.
Records are necessary not only to respond to criticism, but to assure continuity. Accurate documents of improvements, to include construction and equipment warranties, detailed descriptions
of accomplishments, dates of completion, and names and addresses of engineers and contractors inVOlved, will be invaluable in making the pavement management program even more effective
in the future. 1-5 
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􀁾􀁾􀁾􀁎________________􀁾________________􀁾_________ NN _____ _______NN _____Airport Pavement Inspection by PCI CHAPTER 2 PAVEMENT EVALUATION AND MANAGEMENT SYSTEMS INTRODUCTION Public
officials are becoming more aware of a need to manage pavement systems systematically and objectively. As facilities age and as their condition deteriorates, it is apparent that scarce
available funds must be appropriated wisely if the systems, which represent a major capital investment, are to be preserved in serviceable condition. There has been a rapid growth in
Pavement Management Systems (PMS) being offered. While each offers certain positive characteristics, many are limited in scope, flexibility and adaptability to individual needs. Some
are based extensively on proprietary processes, further limiting their long term usefulness. In order to achieve maximum long term utility, a PMS should be flexible enough to incorporate
services specifically selected to meet the User's needs. A PMS should be specifically designed for for an individual pavement system. In addition, when a private vendor or consultant
is involved, the supplier of the PMS must be able to provide professionals with experience and expertise to select appropriate courses of action and appropriate specialized services
from the PMS field. This approach assures that the User will not pay for .more or less than is required, and that the right technology and management tools are acquired for the system.
Further, a PMS should consist of widely accepted procedures which can, to the greatest possible extent, be updated and maintained by the User. Design of an appropriate pavement management
system is a process of integration of all applicable elements. In overview, a comprehensive PMS is a complex integration of technologies which should encompass at least the following
elements, molded into a program that is right for the User. 2-1 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾* System Inventory*
Visual Inspection * Nondestructive Testing* Other Testing* Integration and Evaluation of Data * Capital Expenditure Planning* Maintenance Programming A brief discussion of each of these
elements follows. SYSTEM INVENTORY This critical element of a PMS consists of assembling a historical record of pavement including type, age, construction characteristics and major traffic
considerations. Information is usually available in Owner's files, but historical records of pavement systems are often incomplete. Supplemental information may be available from engineers
who have designed projects, and from the FAA District or Regional Engineering Office. The inventory leads to identification of discrete pavement "sections" having generally similar characteristics.
This process of subdividing pavement allows inspection, testing and evaluation work to be focused more effectively, and facilitates identification of unusual or uncharacteristic conditions.
The system inventory will frequently include a preliminary visual inspection by an experienced pavement engineer to verify conditions and to identify areas of pavement which may require
special attention in the inspection or testing phases. VISUAL INSPECTION Visual inspection is, in reality, an element of the data cOllection phase of a system inventory. It is the oldest
form of pavement condition evaluation. Engineers have been evaluating pavement by this method since shortly after the first pavement was constructed. The greatest difficulty with visual
examination has always been the subjective nature of the process. In recognition of this limitation, an objective system of examination has been introduced which is rapidly ,,, .J. 2-2

Airport Pavement Inspection by PCI becoming a "de facto" standard for visual inspection. This data gathering procedure is a visual inspection system called the Pavement Condition Index
(PCI). The procedure was developed for the u.s. Air Force by the Army Corps of Engineers. It has been adopted by the Federal Aviation Administration (FAA) for use on civil airports.
The system has also become the recommended PMS of the American Public Works Association (APWA) as part of its "PAVER" program for municipalities. A PCI inspection is conducted on a statistically
selected number of samples of each pavement section. While this technique does not give 100% area coverage, the process does provide measured distress information for a large selection
of distress types in the system. This allows reassessment in future years and offers a positive means of determining rate of pavement deterioration. Accordingly, the longer the PMS is
used, the greater will be confidence in the projected life and in the Capital Planning Program. The PCI is based on a number of distinct distress types commonly found in pavements, as
follows: RIGID PAVEMENTS 1. Blowup 10. Scaling, Map 2. Corner Break Cracking, and 3. Longitudinal, Transverse, Crazing Diagonal Cracking 11. Settlement or 4. Durability ("D") Cracking
Faulting 5. Joint Seal Damage 12. Shattered Slab 6. Patching, Small 13. Shrinkage Cracks 7. Patching, Large 14. Joint Spalling 8. Popouts 15. Corner 9. Pumping Spalling FLEXIBLE PAVEMENTS
1. Alligator Cracking 9. Oil Spillage 2. Bleeding 10. Patching 3. Block Cracking 11. Polished Aggr 4. Corrugation 12. Raveling and 5. Depression Weathering 6. Jet Blast Erosion 13. Rutting
7. Joint Reflection 14. Shoving by PCC Cracking Slabs 8. Longitudinal and Transverse 15. Slippage Cracking Cracking 16. Swell 2-3 
􀁟􀁎􀁾􀁎________________________________________________________________Airport Pavement Inspection by PCI The PCI procedure objectively defines the type, quantity and severity of these
distress types in pavement. This data is converted by formula to a numerical rating between zero and 100, with 100 being a perfect pavement and zero being a totally failed pavement.
Accordingly, the procedure affords the User a standard index of pavement condition not available in any of the more subjective inspection procedures. There are three primary objectives
for a pavement condition survey. The first of these is to provide a measure of existing conditions based on apparent structural adequacy and surface characteristics. With training, an
observer can learn much about the causes of pavement distress by evaluating the different types, quantities and severities of distress. The second objective is to standardize procedures
to a degree which will allow the process to be repeated with consistent results, and to assess effectiveness of maintenance programs. The third objective is a common index for comparison
of pavement sections in a system, and to provide a sound basis for maintenance and rehabilitation decisions. The PCI procedure fUlfills these objectives and, in addition, indirectly
measures several primary determinants of pavement condition, including: 1. Structural adequacy 2. Roughness 3. Friction characteristics 4. Rate of deterioration 5. Maintenance effectiveness
This objective distress information can be used directly in maintenance planning and it provides a basis for much of the evaluation procedure discussed later. PCI inspection is an important
activity that provides data for alternative analysis, service life forecasts, reinspection comparisons, and evaluation of pavement deterioration over time. PCI data also provides definitive
information of pavement condition for use in capacity analysis. 2-4 
__ 􀁾_____NNN _____NN ______N _________ N __ 􀁾􀁾_______________ ______________Airport Pavement Inspection by PCI NONDESTRUCTIVE TESTING There are many kinds of nondestructive testing.
In fact, many PMS systems are based nearly exclusively on nondestructive testing procedures. Each type of nondestructive testing has specific application and different types are frequently
used to supplement one another. No single technique, however, can provide all the data necessary for a comprehensive, effective PMS. In a comprehensive PMS program, selection of type
and extent of nondestructive testing should only be made following a review of program objectives and a visual examination of the pavement system. This permits selection of testing procedures
tailored to User needs and observed conditions, and assures that the User pays only for testing programs which are appropriate and necessary. Among nondestructive techniques frequently
employed in pavement evaluation/management programs are deflection testing, ground penetrating radar, infrared thermography and friction testing. Each has a specific function and each
should be selected according to the specific needs of the pavement system. A summary review of some of the most commonly used nondestructive testing techniques is presented here. DEFLECTION
TESTING Equipment Several types of deflection testing devices are in current use. In broad terms, they fall into one of three categories: static devices, dynamic devices and impulse
devices. Static devices, typified by the "Benkleman Beam" are simplest to use and are least costly in terms of capital expense. Unfortunately, they are also most limited in application,
most inconvenient, and most labor intensive of the alternatives. Simply put, use of a static device consists of placing a long fixed beam which extends from outside the test area into
the area where deflection will be measured. A load is placed in the test area, typically a loaded truck, the measuring devices are zeroed, the truck is removed, and the "rebound" of
the the pavement is measured. The process may also be used in the reverse direction. While there is a considerable body of literature attending this process, it is rapidly disappearing
from use because of its labor cost, lack of repeatability in results, and the need to disrupt traffic. 2-5 
􀁾􀁾___N __ 􀁾􀀠__ N ____􀁾􀁟􀁎____􀁾___N ____􀁾____􀁾_____􀁾________Airport Pavement Inspection by PCI Dynamic devices are those which apply a repeated or cyclical load to the pavement
surface and measure pavement response (deflection) with a series of sensors similar to those used in seismic work. Dynamic devices fall into two categories, mechanical and hydraulic.
Mechanical systems have been in use longer, and they function by rotating an eccentric mass about a shaft, imparting a repetitive load to the pavement surface through a wheel, shoe or
plate. Typical of these is the "Dynaflect" machine. Up to this point, there has been more research and more applications completed with this type of device than with any other. It is
in fairly wide use by many public agencies and private firms. Though widely used, the Dynaflect Machine machine has some limitations Figure 2-1 which inhibit its application. One of
these is that it employs a small load, typically 2 Kips or less. While there have been many studies which indicate correlation of pavement response to this type of load with higher loads,
the fact is that for many heavier pavement sections, the device is not capable of generating enough deflection to secure reliable, repeatable data. Another limitation centers on data
analysis. Most applications apply empirical methods which result in "inches of overlay", or linear elastic layer models which analyze materials properties in terms of resilient modulus.
With most common empirical methods, the recipient is usually provided with an end product which provides no clear indication of the method by which a particular result was generated.
In either case, insitu characteristics may exist, relative to load or frequency response, which will result in spurious data. This type of machine, unfortunately, does not have a capability
to vary either load or frequency of application. Since pavements are, in actuality, neither elastic, linear in response, or independent of harmonic influence, it is important to Users
to understand understand these variables and to understand precisely how results were obtained. In spite of these limitations, this type of deflection 2-6 
___N_NN _____________________________________________________________Airport Pavement Inspection by PCI , device may well be the one of choice for relatively ,i light pavement systems
because of ready availability and low cost. In recognition of these limitations, another type of dynamic device has been developed, typified by the "Road Rater". With this machine, load
is applied hydraulically to the pavement, through a plate or shoe, and response is measured through a series of sensors, spaced at uniform distances from the point of load. The advantages
of this type of device are: larger imparted loads (up to 10 Kips); ability to vary load and to "sweep" loads across a range to examine linearity of response; and ability to vary frequency
of load application to Road Rater eliminate harmonic effect Figure 2-1 from the final data. Data analysis is typically either on empirical or elastic layer basis, as withthe mechanical devices. The newest of the devices employed for deflection testing operates on a somewhat different principle. This device is of the "impulse" type which makes a single
application of load by dropping a mass and transmitting the load to the pavement through a plate or shoe. As with the "Road Rater", response is measured through a series of sensors.
These impulse type devices are categorized as "falling weight deflectometers"(FWD). Applied load is variable, determined by Falling Weight Deflectometer the height of the Figure 2-3
drop, and reaches up 2-7 
_____ 􀁾__N __N ___________􀁾􀁎___________􀁾__􀁾__􀁾____ N ______________􀁾_____Airport Pavement Inspection by PCI to 30+ Kips in some machines. although 20-22 Kips is a more typical
upper range. The larger load. at least in theory. more closely approximates heavy wheel loads. an obvious advantage. Applications of this type of deflection test are far fewer than applications
of dynamic devices, but the system is enjoying a fast growing popularity. There is also a considerable amount of research being conducted with this type of device to develop more sophisticated
analytical models. While there is considerable variation in deflection test devices, each can be effective if appropriately applied as an engineering tool based on a thorough understanding
of the data generated, and not on a "black box" cure-all for pavement evaluation. A rule of thumb for applicability might be as follows: Light flexible pavements: Mechanical dynamic
Medium to heavy flexible or medium rigid pavements: Hydraulic dynamic Heavy rigid rigid pavements: Falling weight deflectometer with the understanding that each device can be used for
lighter weight pavements depending on cost and availability. Methodology Two primary analytical methodologies are used in computer programs which predict materials strength based on
deflection data. Most comparative results indicate that either "elastic layer" or "finite element" analysis can produce reliable results. The two approaches are significantly different
but, from a practical standpoint. either can be used with confidence. Other proprietary, or strictly empirical "inches of overlay" analyses based on deflection testing alone should be
used with great caution. The recommended procedure for strength analysis and materials characterization is to combine deflection data and pavement layer thickness information into an
elastic layer evaluation to establish a dynamic elastic modulus for each pavement layer. Elastic layer analysis is preferred because of the extensive body of research data available
in support of results, and because this type of analysis approximates design standards and criteria of a majority of public agencies and trade institutions. Microcomputer programs are
available which produce consistent results with demonstrated accuracies well 2-8 
__________ N_NN ____ 􀁾􀁎􀁾􀁎􀁎􀁟􀁾__NNN ___ 􀁾􀁟􀁎􀁎􀁎__􀁾__ N _______________________ _Airport Pavement Inspection by PCI within tolerances required for pavement applications. From
a technical standpoint. results obtained from appropriately applied elastic layer and finite element analyses have been shown to be comparable within limits of accuracy of deflection
sensors. Users of deflection testing techniques should not be overly concerned about the complexity of analytical models, except in research applications. It is far more important to
achieve a high level of accuracy in testing and analysis by use of available complementary procedures. and to have competent consultation in application of results. GROUND PENETRATING
RADAR One of the most critical elements in the accurate interpretation of deflection test results is accurate pavement layer thickness data. Elastic layer analysis is very sensitive
to layer thickness. Moduli may vary by several hundred percent. based on the thickness value used. In fact. fact. under extreme circumstances. the moduli produced by such analysis can
vary up to one hundred percent with a thickness variation of only one inch. This sensitivity is illustrated in the following figures taken from an actual field project. In each case
deflection data is real and thickness data is varied in one inch increments. The impact of inaccurate thickness information can be readily seen. As these figures are viewed. keep in
mind that actual layer thickness may differ significantly from dimensions shown on record drawings. Variations of five inches and more are common. Figure 2-4 shows the effect of varying
overlay thickness on a fixed PCC slab which is 9" thick. 2-9 
􀁎􀁎􀁟􀁾􀁎􀁟􀁾􀁎􀁟􀁎􀁎􀁟􀁾􀁎􀁎􀁟􀁎􀁎__N __ 􀁎􀁟􀁾__________ 􀁾____________________ 􀁎􀁾_______ 􀁾􀁟Airport Pavement Inspection by PCI 􀁾...............................................................
................................................................... 􀁥􀁌􀀭􀀭􀀭􀀱􀀾􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀱􀁯__􀀭􀀭􀀭􀀭􀀭􀀭􀁉􀁾􀂷􀀭􀀭􀀭􀀭􀀭􀀭􀀻􀁾􀁾􀂷􀀭􀀭􀀭􀀭􀀭􀀭􀀧􀀳􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀱􀀬􀁾􀀧􀁾􀀭􀀭􀁾􀀠DUERLAV
DEPTH Dti-9" pee• CflLC • FROM DEFLECT Variable Overlay on Fixed PCC Figure 2-4 Figure 2-5 shows a similar effect when the overlay is held to a fixed thickness and the underlying PCC
slab thickness is varied. ;..:..-..=, ..........•......,...........................................................................,..........,........·····H'·····..· e-' :. " ............􀀬􀀮􀀮􀀺􀁾�
�􀀧􀀬􀀮􀁾􀀺􀁾􀁾􀀮􀀺... .... ................. .............................................-." ......"..... ,................... 􀁾􀀠Q 7 .........................:r..􀁾􀀺􀀮􀀺􀀮􀀺􀀠...................
.........................................."...................................,' ",... ...... '" 5==UJ 􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀁾􀀺􀁾􀀺􀁾􀀼􀀺􀁾􀁾􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺
􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺 -' 4W .,.w .J.:..:: 􀀮􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀮􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀮􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀁾􀀺􀁾􀀺􀀺􀀭􀀧􀁾􀀽􀀽􀀻􀀺􀁾􀀢􀀢􀀧􀀽􀀺􀀺􀀺􀀺􀀮􀀺􀀺 <.,(1 -'=' ... 1LLI
lEI i.:> i b ':! 1\:1 11 8" OUERLA'( ON UARIAElLE: pee • CMLC. FROM DEFLECT Fixed Overlay on Variable PCC Figure 2-5 The composite effect with both overlay and PCC slab thickness being
varied (a typical field condition) is shown in figure 2-6. 􀀷􀁲􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀠 : 􀁾􀀺􀀺􀀺􀀺􀀺􀁾􀀺􀀼􀀺􀀽􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀮􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺�
�􀀺􀀺􀀺􀀺􀀮􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀺􀀠 4 3 􀁾􀀠<II! 1 􀁾􀀠.....................................􀀺􀀺􀀺􀀺􀀭􀀺􀀺􀀺􀀧􀀺􀀧􀀻􀀧􀁾.....................................................
.................... . -----.... ...................................................................􀁾.................................................... -------.....-􀂷􀂷􀂷􀂷􀂷􀁾􀂷􀁾􀂷􀂷􀂷􀂷􀂷􀂷􀂷�
�􀂷􀂷􀂷􀂷􀀬􀂷..«t····..,·•.••.H ..................................................' •••••••••••••􀀺􀀺􀀭􀁾􀀬....., •• ••• 2-10 
􀁾􀀠􀁾􀁾 ____N_NN _____NN __ ____N ________N _______________________ __________ _Airport Pavement Inspection by PCI , 􀀲􀀰􀁲􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾<I>
:3 1..,=' c:. ''\.Q..;. .... ::: ...................... , 􀁾􀀺􀀾􀁾................................................................................................... I£!I.U ...J ...........
"UJ W 􀀢􀀢􀀧􀁾􀀠...._-...'" .., (to... -..........----W 􀀭􀀮􀀭􀁾􀀭..􀁥􀁌􀁾􀁾􀁾􀀭􀀭􀀰􀀰􀁾􀀭􀀭􀁾􀁾􀀭􀀭􀀭􀀮􀁾􀁲􀀭􀀭􀀮􀁾􀁮􀁲􀀭􀀭􀁾􀂷􀁾􀁾􀁾􀀢􀀢􀀧􀁉􀀻􀀺􀀮􀀠E·/' i • ./..../1 UARIABlE: QIJE:RlAV/UARIABlE•
􀁃􀁾􀁬􀁃􀀮􀀠FROM DEFLECT variable Overlay on Variable PCC Figure 2-6 Since resilient modulus and flexural strength bear a site/material specific relationship to one another. the total
potential effect of either an overdesign or underdesign can be shown in Figure 2-7. in which overlay thickness is determined according to FAA standards. using the approximate range of
flexural strengths which correspond to the previous results. ,. 24r---------------------------____􀁾􀀠I)) 􀁲􀁾􀀠..􀁾f.::! 􀀢􀁾􀀧􀁜􀀮􀁾􀁍..􀁾•._ ....... ......... 1:, r....."...............,..........
.....􀀡􀀺􀀢􀀺􀁾􀀴􀀬􀀻􀀻􀀻􀀺􀁾􀀺􀀺􀀬..,.......,..........................................,.......,............ .􀁾􀀠.......􀁾......"'-..-.------..._-.... 􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀀠Combined
Effect of Errors in Thickness Estimates Figure 2-7 2-11 
___N ________________􀁾__􀁾________N _____________􀁾_______ ______________Airport Pavement Inspection by PCI Ground Penetrating Radar (GPR), supplements deflection testing by providing
accurate layer thickness information for use in the computer model. This technique should be used to complement deflection data unless historical information is known to be consistently
accurate, or where data is being used only to evaluate subgrade characteristics. ; GPR Antenna Configuration GPR Recorded Output Figure 2-8 Figure 2-9 In addition to its application
as a supplement to deflection testing, ground penetrating radar should be the primary tool for locating and mapping voids under pavement. When used in a ground-coupled mode at high center
frequencies, it is acknowledged to be the most accurate nondestructive technique available for identifying and quantifying voids in and under pavement. Accurate dimensional information
is available with GPR and, further, the equipment is capable of discriminating between actual voids and areas where weak or minimal base or subgrade support is present. Other devices
frequently promoted for voids detection are unable to make this distinction. Further, if and when voids can be detected by other means such as deflection testing, estimation of void
size is limited to interpretation of the "deflection basin" defined by sensor measurements. Such estimates are quite unreliable in horizontal dimension, and the technique is incapable
of estimating vertical dimensions of a void. Although some research is being conducted in this area, Users should be aware that these limitations render void 2-12 
___ N _____________________________ 􀁎􀁎􀁟􀁾_______________________􀁾_______Airport Pavement Inspection by PCI detection by deflection testing currently unproven methodology. as a speculative
and Finally, where load transfer is consideration, GPR provides a direct deterioration characteristics such as versus keyway failure. an important reading of joint durability failure
THERMAL INFRARED THERMOGRAPHY Yet another nondestructive technique which has application in pavement evaluation is infrared thermography (IR). Although IR was developed primarily for
rapid, accurate detection of delamination in bridge decks, the technology has found more general application on pavement for several years. IR Camera Configuration IR Image on Pavement
Figure 2-Hl Figure 2-11 The major application in pavement evaluation has been detection of corrosion induced delamination in reinforced concrete pavements, particularly on continuously
reinforced concrete pavement (CRCP). Recently, however, IR has been successfully employed in such diverse projects as mapping asphalt overlay debonding, and location of bond failures
in porous friction courses. Primary advantages of this technique are rapid data acquisition, minimum traffic interference, and a degree of accuracy not attainable by manual or mechanical
acoustical means. 2-13 
Airport Pavement Inspection by PCI SKID RESISTANCE (FRICTION) TESTING Skid testing is one of the oldest forms of nondestructive testing for airfield pavements. Much of the current equipment
has been in use and continued development for years. This procedure is designed to provide a numerical assessment of the friction characteristics of the pavement/tire interface Mu-Meter
under both wet and dry condi-Friction Testing Device tions. The most typical Figure 2-12 characteristics under a wetted or flooded condition, and continuously over time following wetting,
to assess friction charactgeristics as the pavement dries. The same devices can be, and often are, used to measure braking qualities under icing conditions. There is a large body of
existing literature on this procedure. ,OTHER TESTING ) Depending on specific project requirements, other types of testing may be required. These may include laboratory testing of pavement
core samples, subsurface exploration, and field or laboratory determination of bearing capacities. It is important to employ such teChniques only after preliminary analysis of data gathered
in the visual inspection and nondestructive testing phases of the project, and to a limited extent, for calibration of nondestructive test results. This procedure assures the User that
such additional testing will be properly focused and attendant costs will be held to a minimum. COMPUTERIZED EVALUATION The dominant analytical tool in pavement evaluation/management
systems is the microcomputer. Many programs being offered today present a single maintenance or rehabilitation strategy which may be accepted or rejected by the User. This limited approach
is typical of early attempts at computer analysis. ./2-14 
____􀁎􀁎􀁾􀁎􀁾_____NN __􀁾􀁾􀁟􀁾___N ____ 􀁾􀁟􀁎􀁎􀁎􀁟􀁾_____NN _____________N_N _______ 􀁾Airport Pavement Inspection by PCI The most highly publicized recent entry into the PMS ) computer
systems environment is MicroPAVER. MicroPAVER is a modification of mainframe PAVER software developed by the Corps of Engineers for the Federal Aviation Administration and the Air Force.
MicroPAVER software operates on desktop computers. The most attractive feature of MicroPAVER is that it is inexpensive and available, by subscription, to anyone. Disadvantages, however,
may be more important to the User. First, MicroPAVER is canned software. Written in the 1970s, programming techniques are dated and cumbersome. Programs are generic, so interaction required
by the User is extensive. Potential for modification to meet the Users needs is very limited, as software is "off the shelf" to PMS consultants, not written by them. Second, MicroPAVER
software is memory intensive and time consuming. The MicroPAVER program alone, exclusive of memory or data requirements, uses in excess of eight megabytes of storage capacity. Although
the Corps has developed some techniques to make MicroPAVER more efficient and "user friendly", implementation of a pavement system PMS requires considerable expertise and time commitment
by the User. Eckrose/Green's AIRPAV pavement evaluation & management software, on the other hand, is menu driven and modular, allowing the user to acquire only those portions desired
for in-house use. Use of the software does not require high levels of computer expertise or memorization of unique commands. AIRPAV software was developed using most recent innovations
in programming technique so that computations are fast, and storage and memory requirements are minimized. Basic AIRPAV module classifications are: (1) PCI data storage and calculation1
(2) analysis of pavement characteristics and development of improvement options; and (3) creation and interactive use of Capital Improvements recommendations for individual airports
airports and the state network. Since these functions are not carried on simultaneously, the user only needs memory capacity for one activity at a time. A summary of memory requirements
for these three functions follows: ACTIVITY PROGRAM OVERHEAD TOTAL REQUIREMENT REQUIREMENT REQUIREMENT PCI CALC. 73 KB 58 KB 131 KB ANALYSIS 70 KB 58 KB 128 KB CAP. IMP. 81 KB 58 KB
139 KB 2-15 
􀁾__􀁾_______ N _______________________ 􀁾__________________________N _____Airport Pavement Inspection by PCI As can be seen, any of the AIRPAV programs can operate in a 256 KB RAM environment.
However, we recommend a minimum of 512 KB, with 640 KB preferred, for fastest and most convenient operation of the system. Mass data storage is another consideration in viewing hardware
requirements. AIRPAV software is designed to use mass storage for only the data portion actually required to support the function. This assures minimum operator inconvenience, particularly
where the system configuration relies on diskettes for mass data storage. A third disadvantage of MicroPAVER is that it does not have the degree of sophistication in evaluation that
is evident in Eckrose/Green AIRPAV software. Comparisons are offered below. MicroPAVER forecasts pavement deterioration based on straight line analysis from date of construction to date
of inspection to date of forecast. In contrast, AIRPAV forecasts are made using fourth order forecast curves representing actual inspection data within the airport system under evaluation.
If insufficient data is available from the system evaluation for reliable curve development, the AIRPAV generic data base consisting of more than 300 airport inspections may be utilized.
\ MicroPAVER programs corrective actions and estimates using unit prices provided by the user, and recommendations based on Pavement Condition Index ranges. AIRPAV recommendations and
estimates are based on a matrix of actual distress types, severities and densities, not PCI values. The results are much more compatible with pavement conditions. MicroPAVER prepares
Capital Improvement Programs based on maintenance and rehabilitation actions specially input by the user. MicroPAVER does not offer alternative actions unless such actions are specifically
input by the user. In effect, MicroPAVER manages a data base and performs some mathematical calculations. AIRPAV software, on the other hand, anticipates needed actions based on pavement
conditions as indicated by recorded distress information. Using the matrix described above, the program recommends a best corrective action, and presents all alternative actions which
will result in increased service life for the pavement, from among the following potential alternatives. Each flexible pavement action is independent. However, four of the rigid pavement
actions may be chosen in combination. Therefore, seventeen options are actually evaluated for rigid pavement. 2-16 
Airport Pavement Inspection by PCI FLEXIBLE PAVEMENT RIGID PAVEMENT Reconstruction Structural Overlay Resurfacing Surface Treatment Repair No Action Reconstruction Reseating/Overlay
*Slab Replacement *Patching Crack *Joint/Crack Repair *Undersealing No Action *Coactions.mbination In additiEckrose/on to Green evaluating AIRPAV software rehabilitation options, forecasts
service life extensions and estimates costs for each action presented. AIRPAV software is much faster in operation than MicroPAVER. This difference can best be appreciated by working
with the software, but some comparisons can be made in hard numbers. First, AIRPAV makes extensive use of RAMDISK to speed applications. RAMDISK is typically 90-120 times faster than
hard disk in a typical XT class microcomputer. The size of the MicroPAVER program does not permit use of RAMDISK in most computers, even though they may have been designed for such use.
A second factor which contributes significantly to the speed of AIRPAV is in disk file efficiency. The more times a computer program must access the hard disk, the slower it will run.
By comparison, using data from a small Indiana airport, MicroPAVER required 1241 disk access operations just to generate a maintenance report on the screen. AIRPAV used only 1144 disk
access operations to access data, analyze each feature, select viable alternatives, project service life for each, optimize project years, and store resultant information into the Capital
Improvements Program. A similar task-to-task comparison was conducted for a single feature on the airport to retrieve maintenance and repair information. MicroPAVER required 866 disk
access operations. AIRPAV required only 161, of which 92 were to the highly efficient RAMDISK. To reduce these comparative statistics to terms which can be immediately appreciated by
any pavement manager, the following example is presented. Identical inspection data from a small general aviation airport was input to MicroPAVER and AIRPAV computer programs. The same
computer was used, and data was entered by the same operator, who is experienced in use of both systems. Time required by MicroPAVER, to obtain PCI values for 2-17 
􀁾􀁎􀁎___􀁾__ N_N_N _________􀁾________􀁾􀁟􀁾______􀁾__________Airport Pavement Inspection by PCI pavement on the airport, was two hours and thirty minutes. Time required by AlRPAV,
to accomplish the same task, was less than thirty minutes. Use of AlRPAV software does not require high levels of computer expertise or memorization of unique commands. Complete operating
manuals are provided for individual modules or for an integrated system, dependent on user selection. The modules used in preparation and installation of a Pavement Management system
are briefly described as fOllows: AlRPCl -This module reduces field inspection notes to standard PCl reporting sheets and creates an electronic record of all inspection activities. Provisions
are made in the program for distress types, severities, quantities, resultant deduct values and calculated PCI values. The program is used to create a pavement condition data base. This
data base is maintained independently from all successive uses, in order that future updates of inspection data will not be adversely affected by other activities. AlRPMS -This program
automatically reads pavement condition data from the PCI file, accumulates data by facility and feature, and produces a working data base format. Pavement ratings are calculated by feature
and extrapolated distress quantities are developed. The program provides for additional storage of data such as construction history, test results, etc. Supplemental data storage can
be tailored to the User's needs and desires. This program is also the basic analytical tool, providing either on-screen graphic analysis or hard copy presentation of recommended alternatives,
as noted in the software descriptions. Analysis may be conducted for any year and the results will be added to the data base at the user's option. Analysis can be done for a variety
of Minimum Service Levels. Transfer to the AIRCIP module is done by simple menu selection. 2-18 
____NNN __NNN ________________________________________________________Airport Pavement Inspection by PCI Graphic Display of AIRPMS Alternatives Figure 2-13 AIRCIP -This is the "standard"
recommended module for user installation. This program uses the alternative recommendations from the AIRPMS analysis for development of Capital Improvement Programs for a six year period.
The User controls such items as unit costs and inflation factors in the development of these programs. Further. the User can move projects from year to year. with automatic cost recalculation
and service life revision. and can upgrade or downgrade project scope, within the limits of viability established in the AIRPMS analysis, again with automatic recalculation of cost and
expected service life. AIRCIP provides access to Master File data to perform the following functions. 1) Maintain up to 10 alternative eIP scenarios 2) Review data file 3) Display data
in any of several categories 4) Review and change unit prices 5) Review and change rate of inflation 6) Evaluate action alternatives 7) Evaluate consequences of delayed action 8) Develop
projects of like action among sections 9) Move prOjects to alternate years 10) Display six years of recommended improvement 11) Add user-selected projects not previously analyzed 12)
Combine several airport programs into a statewide CIP 13) Print any of the above displays 2-19 
____________________N __________________􀁾__􀁾_________􀁾_ ____________􀁾􀁟􀀠Airport Pavement Inspection by PCI AIRCIP On-Screen Display Figure 2-14 Transfer back to the AIRPMS module
is by simple menu selection, if that module is installed. In addition to construction of improvement programs, the program provides for pavement ranking by age, by condition, or by condition
relative to minimum service level. Other ranking formats can be made available. AIRMIP -This Maintenance Improvement Program is the newest addition to the Eckrose/Green library of computer
software. AIRMIP reads distress information and formulates maintenance strategies for implemention by airport personnel. Only distress types correctable "in-house" are considered. The
scope of AIRMIP is based on capailities of maintenance personnel and the maintenance philosophy of management. Distress types normally considered are reflective and shrinkage cracks
in flexible pavement, and joints and cracks in rigid pavement. Patching may also be included included where maintenance personnel have capability to work with hot mixed asphalt concrete
and Portland cement concrete in small quantities. Less frequently, surface treatments are considered in AIRMIP where equipment and expertise are available on staff. AIRMIP estimates
distress quantities, calculates amount and cost of materials required, and estimates manhours and equipment. Maintenance activities are subdivided into Urestorativel!, "sustaining",
and "interim" categories. Each has different specifications and resource requirements. Activities are also divided by type, including "crack repair", "joint repair", "asphalt 2-20 
􀁎􀁾􀁎􀁾􀁎􀁎􀁎􀁎􀁎____ 􀁾􀁾􀁾________N __ 􀁾􀁾___ 􀁾􀁟􀁾___ N_N ______ 􀁾􀁾_____ ______________Airport Pavement Inspection by PCI patching", "PCC patching", and where appropriate, "surface
treatment". Slab replacement might also be included at the discretion of airport management. AIRMIP presents maintenance opportunities, by pavement facility, and by maintenance category
and type, in the form of a Maintenance Work Plan. Maintenance Work Plans are designed to become Maintenance Work Orders when authorized by maintenance supervisors. AIRCAP -Where indicated,
especially in pavement at commercial service airports, capacity analysis, may be included in the comprehensive evaluation. Capacity analysis is a predesign function which allows the
User to rapidly view structural capacity of pavement under existing or forecast traffic. For such pavements, use of a microcomputer based program which provides rapid assessment of capacity
is essential. AIRCAP designs a theoretical structural overlay for each section of pavement using existing in-place materials as the foundation, and actual, or forecast, traffic loads.
The result may be a "plus", "minus", or "zero" value. A zero indicates existing pavement is exactly balanced to aircraft loads. A plus overlay indicates pavement which is not structurally
adequate, and a minus overlay indicates pavement which has capacity in excess of aircraft loads. This approach to capacity analysis allows a design engineer to visualize the degree of
"imbalance" in a pavement system, and to plan and design projects to restore that balance. Ultimately, the AIRCAP program makes possible a most economical design for rehabilitation of
airfield pavement. Each pavement section is analyzed separately, taking maximum advantage of known conditions. Pavement sections are then compared for load vs. capacity imbalance. A
rehabilitation strategy can then be developed to provide just the right capacity for each pavement section while making best use of existing material strength. This approach is equally
beneficial for all pavement types. The AIRCAP program has many features which can be particularly useful to a design engineer. They include: * Automatic calculation of design aircraft.
The program allows for entry of any combination of aircraft types and departures. up to 45 types of aircraft can be used in determination of a design aircraft, and the library of landing
gear configurations and weights can be customized to reflect 2-21 
N __N ___N __ 􀁾___N ____􀁾_________􀁾􀀠_______􀁾_______􀁾______􀁾_ ______________Airport Pavement Inspection by PCI * * * * special aircraft on any airfield. This feature allows a rapid
evaluation of potential impact of changes in air traffic mix, as well as anticipated changes in ground movements. Consideration of subgrade strength. Where known values for subgrade
strength are available they can be used. In other cases, this information can be provided through conventional or nondestructive testing. Since the program uses approved design procedures,
sensitivity of pavement to subgrade conditions can be readily assessed and a cost effective program of additional testing can be developed based on need. Incorporation of Pavement Condition.
The program essentially designs a pavement and an overlay, if required, using existing materials and based on eXisting pavement conditions. Therefore, the capacity analysis accurately
reflects pavement condition and traffic loads. The program is capable of using pavement condition information from PCI surveys and from both nondestructive and destructive testing programs.
An important capability is the ability to couple capacity analysis with service life forecasts from analytical programs to assess future pavement capacity under various rehabilitation
strategies. Operational Considerations. Critical operation patterns and loadings can be compared to pavement capacity. This allows for rapid identification of pavement areas which may
require load restrictions, and provides an ability to relate potential shortterm and long-term traffic flow changes to pavement capacity and rate of deterioration. Program Timing. Pavement
does not deteriorate at a constant rate. Most evaluation programs do not recognize this fact, or do so only in a limited fashion. A realistic analysis must be able to analyze the effect
of project timing on costs and on ability of pavement to withstand traffic loads. This capability will provide the User with a most meaningful long-term improvement plan. 2-22 
_NN ____NN ____􀁾__NN _____NN _____________________N _______ ______________Airport Pavement Inspection by PCI ) 􀁓􀁕􀁾􀁙􀀠A Comprehensive Pavement Evaluation/Management Program is a
complex and interdisciplinary activity. Each program should be tailored to User needs. Fortunately, procedures and technologies are rapidly being developed which can assist the User
to implement such a program. Current microcomuter technology permits easy integration of these techniques. 2-23 
/
____ 􀁎􀁾_______ NN _____ NN ____􀁾_____________ 􀁾􀁾________________________ 􀁾__Airport Pavement Inspection by PCI CHAPT£R 3 SITE LAYOUT AND INSPECTION Authors' Note: Detailed descriptions
of pavement distresses and an outline of PCI procedures are presented in FAA Advisory Circular 150/5380-6. "Guidelines and Procedures for Maintenance of Airports". Anyone proposing to
implement. supervise or administer PCI procedures on an airport should study the Advisory Circular carefully. PAVEMENT CONFIGURATION AND HISTORY The first essential step in defining
a pavement system for evaluation is to establish its boundaries and dimensions. Best sources for this information are Airport Layout Plans (ALP). record drawings of construction projects,
and aerial photographs. FAA "5010" inspection sketches may be useful if drawn to approximate scale. If previous surveys of the pavement system have been done. a pavement layout sketch
may be available. The records review must also include an investigation of the construction history of the pavement system. Much of this information is available from records mentioned
above. These records may normally be found at the airport or at State and FAA offices. Important information inclUdes locations and dimensions of pavement construction projects, including
description and thickness of layers placed: and year of last construction. In addition to records research, it may be necessary to visit with local officials to complete the inventory.
At commercial airports serving larger than commuter aircraft. a traffic study may also be required. This may consist of interviews with airport operations personnel, Air Traffic Controllers
and Airline (including cargo carriers) Station Agents. The purpose, initially, is to establish traffic flow patterns to and from runways, and to gates and parking. 3-1 
___N ________________________􀁾_______􀁾_____________􀁾__________________Airport Pavement Inspection by PCI PAVEMENT LAYOUT Before a PCI survey can begin, it is important to make a layout
sketch of the airport pavement, subdividing it by type, composition and function to establish a management network. A layout sketch of the network shows pavement defined by Facilities,
Features and Sample Units. This sketch will be a primaryguide for inspectors and will become a record of the survey. PCI procedures require that pavement be SUbdivided into Facilities,
Features and Sample Units. The purpose, and our technique, of subdividing pavements are as follows. Facilities. A Facility is a readily identifiable pavement segment such as a runway,
taxiway or apron. Facilities should be named pavement segments where so identified. For instance, "Runway 8-26", "Taxiway A" and "Terminal Apron" are examples of individual Facilities
on an airport. We number Facilities using four digit identifiers coded by function. For example, example, taxiway Facilities might be numbered according to letter identifier as follows,
Taxiway A = 11210 Taxiway B 􀁾􀀠200 Taxiway C 􀁾􀀠300, etc. Aprons would begin with a higher series of numbers such as: Terminal Apron = 4100 General Aviation Apron = 4200 Transient
Parking 􀁾􀀠4300, etc. Finally runways would numbers such as: receive a still higher series of Runway 13-31 Runway 4-22 = 6100 = 6200, etc. With this system, the pavement function is
immediately recognizable. Taxiways are l00's through 2000's, aprons are 4000's, and runways are 6000's. Anyone who works with the system will soon come to recognize individual Facilities
by number. And, in a state airport system, numbers can be assigned so that primary runways and terminal aprons are identifiable at a glance. 3-2 
______ _ 􀁾______􀁾_____________________________________________________NAirport Pavement Inspection by PCI This numbering system may be expanded to incorporate new Facilities or to
redesignate existing Facilities without disrupting the logic of the system. Features. A Feature is a pavement section with uniform function, age, composition and condition. A Feature
is always contained within a single Facility. Its purpose is to identify a segment of pavement which can be expected to perform and deteriorate uniformly in service. Feature boundaries
are located at Facility boundaries, construction lines, major traffic intersections, and where pavement conditions change noticeably. A Feature can be as small as a single Sample Unit
(described below) or as large as a Facility. The search for new Feature boundaries continues throughout the inventory and evaluation process. It begins with investigation of pavement
history of the airport. Feature boundaries are located at each construction limit and at each change in pavement type and cross section configuration. Pavement composition and year of
construction are recorded for each Feature. Feature boundaries are noted on the layout sketch. Next, at commercial airports, traffic patterns are examined. Additional Feature boundaries
are located at taxiway intersections having significant convergence or divergence of traffic. Feature boundaries may also be located on aprons where traffic routes are dictated by gate
positions or designated taxi lanes. A data summary sheet is prepared for each Feature in a pavement system. Information includes construction history, pavement area and whether the pavement
is used by larger than commuter aircraft. These Feature summary sheets may be used by inspectors during the survey to analyze probable causes of pavement distress. When new Features
are created, or when Features are modified during a field survey, Feature summary sheets must be updated, accordingly. A sample Feature summary sheet is presented at Appendix A. The
following guidelines will assist in designating Feature boundaries. 1. Construction Feature boundaries have precedence over traffic Feature boundaries. Where a construction boundary
exists within 200 feet of a traffic boundary, designate the construction boundary and ignore the traffic boundary. 3-3 
􀁾􀁾􀁎􀁾􀁾􀁾􀁎􀁎􀁟􀁎􀁟􀁎____N _____________________________________ _ 􀁾_____________Airport Pavement Inspection by PCI 2. Feature boundaries for traffic are not necessary on airports
which do not serve larger than commuter airplanes or cargo type military aircraft. General Aviation aircraft usually have little impact on pavement condition. 3. Do not locate traffic
Feature boundaries at little used connecting taxiways. 4. Analyze ground support vehicle lanes as part of the traffic analysis at general aviation airports. Snow plows and fuel tankers
often cause more damage on pavement at small airports than do aircraft. 5. When in doubt about establishing a traffic Feature boundary, leave it out. If traffic impact is significant,
pavement condition will be affected, and a condition boundary will be established during the survey. Additional Feature boundaries are established during the PCI survey where distinct
changes in pavement condition are found. The final review of Feature boundaries is made during evaluation when PCI values are analyzed. If a sequence of Sample Unit PCI reveals a significant
change in condition within a Feature, a new Feature boundary will be established to separate the two conditions. Features are identified using the last two digits of the Facility number.
For instance, 1525 is Feature number 25 in Facility 1500. When Features are identified on the pavement sketch, they should not be numbered consecutively, but in increments of 3, 5 or
10 so that Features can be added in sequence as the study progresses, and in future surveys. Sample Units. sample Units are the building blocks of PCI pavement management. sample Units
provide control for the PCI survey. They divide pavement into equal or similar size segments and they define specific areas to be inspected. If 100 percent of a pavement system were
to be examined, Sample Units would theoretically not be required. However, an advantage of the PCI method of evaluation is that an entire pavement system can be represented while inspecting
only a a portion of the pavement. The entire pavement system is subdivided into Sample Units. Then a representative sampling of those units is 3-4 
􀁾___________N ___ NNN ___􀁾___________ 􀁾___________ 􀁾___________ 􀁾􀁎_________Airport Pavement Inspection by PCI inspected. Feature PCl are obtained by averaging Sample) Unit PCI
within the Feature. A Sample Unit should contain about 5000 square feet of flexible pavement, or approximately 20 slabs of rigid pavement. Sample Unit size can vary from these standards,
but should be of uniform size within a Feature to the extent possible. uniformity of sample size is especially important for rigid pavement. Sample Units are laid out and numbered following
initial pavement inventory and traffic review. Sample Units may be numbered consecutively in direction of stationing by Facility or, when a Facility is segmented by Features which vary
widely in size and shape, by Feature. When Sample units form adjacent columns within a Facility, numbering begins at the left column with number 100. As numbering of each column is completed,
the next adjacent column is numbered beginning with the next multiple of 100 (i.e. second column begins with 200, third column with 300, etc). This technique offers continuity while
providing for addition of Sample Units in sequence following expansion, or when field adjustment of Facility dimensions is necessary. On a very large Facility, such as an apron with
several columns of Sample Units, an adjustment may be necessary in the numbering procedure. Where the sequence described above is inadequate to supply all Sample Units in a Facility
with a number, the apron should be divided along a Feature line and the sequence repeated. On flexible pavement, Sample Units are normally laid out by stationing in units of 50 or 100
feet. Where width is optional, as on an apron, it is established at 50 feet and length is 100 feet to aChieve the 5000 square foot standard. Where width is dictated by Feature or Facility
boundary, length is established in the 50 foot multiple which will provide an area approaching or equal to the 5000 square foot square feet. Taxiways and except where longitudinal are
subdivided as follows; Facility Width (in feet) up to 25 25 to 50 50 to 100 standard but at least 2500 runways up to 100 feet wide, Feature boundaries control, Sample Unit Length (in
feet) 200 100 50 
􀁾__􀁎􀁟􀁎􀁎􀁾􀁎􀁟􀁾____N_N ___N ___􀁾_________ 􀁾________􀁾________________________Airport Pavement Inspection by PCl Runways and taxiways wider than 100 feet are subdivided longitudinally,
usually in thirds for operational reasons unless longitudinal construction boundaries, such as a widened pavement, prevail. Fillets and radii pavement should be defined as separate Sample
Units, if their area exceeds 2500 square feet, but such odd Sample Units should not normally be selected for inspection unless they are independent Features prescribed by composition,
age or traffic. Where the inspector detects a significant difference in pavement condition at a radius or fillet, he may establish a separate Feature for that pavement, or inspect it
as an additional Sample Unit. On rigid pavement, Sample Unit layout is dictated, to some degree, by individual slab configuration. The standard is 20 slabs per Sample unit. However,
adjustments may be necessary to achieve a balanced layout. For statistical purposes, it is important that all slabs in a Sample unit be of uniform size to the extent possible. Different
Sample Units within a Feature may be of different size and contain different slab count, but the size of each and number of slabs in each must be known. A Sample Unit should not normally
have more than 28 or fewer than twelve slabs. Sample Unit numbers are referred to on layout sketch and in conversation as integers, such as "Sample Unit 226", but they are combined in
analysis with Facility and Feature identifiers as decimals. For instance, Sample Unit number 226 on a Terminal Apron would be identified in analysis as 4110.226, immediately associating
the Sample Unit with Feature 10 in Facility 4100. LAYOUT SKETCH. All pavement in a system should normally be included in the layout sketch. A client may not wish to have all pavement
inspected in the initial program, but the outline should be included where possible. In developing a layout sketch for a pavement system, the following suggestions will be helpful. 3-6

􀁾 ___ __________ N _______________________________________ _____________NNAirport Pavement Inspection by PCI 1. Designate airport name and the date information is current. 2. A scale
of I" '" 200' is about the smallest size which permits "half-sizing" for field work. 3. Orient the drawing with a north arrow. 4. Complete pavement outline from aerial photos, Airport
Layout Plan (ALP) drawings, or construction drawings. FAA 5010 sketches may sometimes be used for pavement outlines. Exact scale is not required in the pavement outline, but the proportions
must be near enough to scale to assure the proper orientation of Features, and the proper number of Sample units in a Feature. 5. subdivide all pavement into Facilities. Use heavier
lines to differentiate Facilities from Sample Units. 6. Subdivide Facilities into Features referring first to construction history, then to traffic. 7. Establish reference lines for
control. Mark stationing lightly on the sketch. (This will be helpful in laying out sample units). All Feature and Sample Unit boundaries must be referenced from lines which are clearly
identifiable on the site, such as pavement edges or extended centerlines of taxiways or runways so that they can be located in the field. 8. Layout Sample Units from reference lines.
Number Sample Units consecutively from one end of a Facility to the the other. 9. Number all Features. 10. Identify runways by number identifier (i.e. Runway 8-26) and taxiways by appropriate
letter or number if so designated. 11. Incorporate all odd sized pavement remnants into Sample Units as follows. a. Fillets and radii constructed as components of surrounding pavement
-include with adjacent Sample Unit if smaller than 2500 square feet (flexible pavement) or fewer than ten equivalent size slabs (rigid pavement). Otherwise designate as a separate Sample
Unit. b. Fillets and radii constructed separately, as at widened sections -designate separate Feature. 3-7 
---------------------------------------------------------------------Airport Pavement Inspection by PCI c", Remnant pavement at end of Sample Unit column Include with adjacent Sample
Unit if less than 2500 square feet. Otherwise designate separate Sample Unit. 12. Dimension odd sized remnants carefully. 13. Dimension all Sample Units. (A single dimension representing
typical Sample Units in a Facility is fine. ) 14. Measure all stationing around taxiway curves on centerline. On flexible pavement make Sample Unit lines perpendicular to centerline.
15. Make all notations large enough to be readable on reduced size reproductions. 16. At Facility crossings, Sample Units of the prominent Facility are shown. Sample Units of the secondary
Facility continue through the prominent Facility, but are not shown. (Numbering continues with stationing as well, as if the secondary Facility is covered by the prominent Facility.)
The prominent Facility is identified by construction continuity. If an intersection is an independent construction Feature, prominence is established by operational preference. 17. On
rigid pavement, show joint configuration and spacing. If consistent, dimensions may be shown at pavement boundaries as typical. If internal variations occur, detailed drawings must be
made to show the variations and their relationship to Sample Units. Several examples of layout sketch details are presented on the following pages. 3-8 
____ 􀁎􀁾􀁎􀁎􀁎______N ____NNN_N _____________NNN ______________ 􀁾______ 􀁾􀁾__N_NAirport Pavement Inspection by PCI LEGEND 100' X 50' 13 100 /-fEATURE -TYPE Of PAVEMENT TYPICAL SAMPLE
UNIT SIZE (LENGTH X WIDTH) NUMBER Of SAMPLE UNITS IN FEATURE 􀁾􀀭􀀭􀀭􀀭NUMBER Of SAMPLE UNITS INSPECTED 􀁾􀀠CROSSED SAMPLE UNITS = SAMPLE UNITS RANDOMLY CHOSEN TO BE INSPECTED 􀁉􀁾􀁉􀀠CIRCLED
SAMPLE UNITS = SAMPLE UNITS INSPECTED * = NUMBER OF SAMPLE UNITS REDUCED <95% CONFIDENCE ATTAINED) + = FEATURE PCI > 90 OR NUMBER OF SAMPLE UNI TS INSPECTED REDUCED TO 10% FEATURE PCI
< 40 Legend Figure 3-1 This is a typical legend for a layout sketch. The information "balloon" presents data needed to plan the field layout and inspection. Symbols used to identify
reduced inspection density represent circumstances described below in the section titles "Representative Sampling". 6 10 1 BIT 100' X 50' 9)1i 35 Sample Unit Layout -Runways and Taxiways
Figure 3-2 Runway Facility number is 6100. Feature number shown is 01. Sample Units begin at end of runway with number 100 and are numbered consecutively. Taxiway Sample Units are numbered
from edge of runway pavement. This permits layout and inspection of taxiway pavement within the runway safety area concurrent with runway inspection, minimizing downtime. 3-9 
􀁟􀁾􀁟􀁾___ N ___ N ______________􀁾________________ 􀁾􀁟􀁾_______________________Airport Pavement Inspection by PCI Sample Unit Layout -Aprons Figure 3-3 Sample Units are numbered consecutively
in columns, with each column beginning with a multiple of 100. This offers numbering continuity in event of apron expansion. Note that taxiway 1901 (new pavement) was not inspected •
... .. .... .... ... .... Sample Unit Layout -Secondary Runway Figure 3-4 Sample Unit layout continues "under" the prominent runway. Since Sample Units are dimensioned in 50 or 100 foot
increments, runway stationing can be determined from Sample Unit numbers. For example, the beginning of Sample Unit 139/339/539 on the prominent runway is at Station 39. 􀁎􀁯􀁴􀁥􀀭􀁲􀁨􀁡􀁾􀁴􀁨􀁥􀀠beg
inning of Sample Unit 164 on the secondary runway is at Station 32, since these Sample Units are only 50 feet long. The prominent runway, which is 150 feet wide is divided into 50 foot
wide Features. The secondary runway, which is 100 feet wide, has a single Feature full width. Note, also, that small fillets at the intersection are incorporated with adjacent Sample
Units and large fillets are designated as separate Sample Units. 3-10 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭REPRESENTATIVE
SAMPLING The PCI procedure requires a thorough, searching inspection. This can be time consuming and expensive. However, the procedure was developed to provide for representative sampling
of pavement to reduce time and cost. The degree of confidence in the survey is a function of sampling density. It remains, then, to decide how many Sample Units to inspect, and in what
distribution. Distribution can be accomplished by random selection or systematic sampling. Random selection, as the name implies, relies on formulas and tables for selection of units
to be inspected. In systematic sampling, a pattern is established within each Feature to provide even distribution of units to be inspected. In systematic sampling it is important to
randomly select the first Sample unit in the pattern to be inspected. Sampling density is another another matter. The confidence level to be expected is a function, not only of density,
but of number of total samples and consistency of pavement condition. These are statistical truths. Two levels of confidence are commonly mentioned in pavement management. project level
confidence requires a high degree of assurance upon which financing and design decisions can be made. Network level confidence is satisfactory for more general management decisions such
as selecting among candidate projects and budgeting for future work. project level confidence is generally established at 95 percent. A chart is provided in FAA AC 150/5280-6 to establish
sampling density required for Features relative to total number of Sample Units and condition of pavement. Project level confidence requires a high sampling density in small areas. The
FAA does not offer a guideline for Network level sampling. However, the following sampling schedule has been very satisfactory in Airport Pavement Evaluations. This schedule normally
results in a sampling density on large airports of 15 to 25 percent, and on small airports of 25 to 35 percent. 3-11 
􀁟􀁎􀁟􀁾_______________N _______________________________________􀁾_________ Airport Pavement Inspection by PCI TABLE 3-1 Recommended Sampling Density Total Samples Samples Inspected
Good Condition Poor Condition 1-2 All All 3-4 2 3 5-7 3 4 8-10 4 5 11-14 5 6 15-19 6 7 20-25 7 7 26-30 8 8 31-37 9 9 38-45 10 10 46-55 11 11 56-80 12 12 Over 80 15% 15% Assignment of
pavement condition in this schedule is subjective and can usually be provided by the airport engineering staff. Although this schedule does not statistically assure 95 percent confidence,
a very representative survey is achieved. Time required to inspect a sample unit, particularly on flexible pavement, is a function of pavement condition. Measuring and recording multiple
distress conditions on pavement which is obviously below the established minimum acceptable service level can be costly, and serves no meaningful purpose. We recommend that, when pavement
can be shown to be below a threshold PCI, say PC! = 40, inspection be terminated in that Feature. Conversely, there is little to be gained from meticulous inspection of very new pavement.
We recommend that pavement constructed within two years prior to the year of survey not be inspected unless there is knowledge of premature deterioration. Finally, on inspected pavement,
we recommend that inspection be terminated when PCI can be shown to be above a designated level, say PCI = 90. 3-12 
􀁾􀁾􀁾____􀁾􀁟􀁎__􀁾􀁾􀁟􀁎_____ 􀁾______ 􀁾_____􀁾_____􀁾__􀁾___Airport Pavement Inspection by PCI ) INSPECTION A team of two persons works well for pavement inspection. Team members
may work independently or together. Each person or team needs a vehicle for mobility on airport and each person should be within hearing distance of an air-to-ground radio receiver set
to the designated frequency. On controlled airports, each person or team must maintain radio contact with the Air Traffic Control Tower (ATCT). Inspection Team Figure 3-5 Survey Vehicle
Figure 3-6 The team approach offers disruption is minimized. several advantages. Surveillance for Traffic airport traffic is improved. Inspectors can discuss types and severities of
distress, and can check each others work to assure best results. A disadvantage is that the team approach is less time efficient than independent operation. Inspectors should work as
a team during the early stages of a project (at least one or two days) to assure standardization. Thereafter, experienced inspectors may work independently, with periodic consultation
to assure consistency. When there is an inexperienced inspector on the project, the team must stay together until full standardization is achieved. Inspectors record data on data sheet
forms. Data sheets must be reviewed by inspectors before leaving an airport to assure that all required Sample Units are represented 3-13 􀁾____ _ 
􀁟􀁾__ 􀁎􀁾____ 􀁾_______􀁾______􀁎􀁾___________________________ ______________ _Airport Pavement Inspection by PCI and to recheck any data entry which appears out of place (inspectors
check each other's work). Copies of sample unit data sheets for flexible and rigid pavement are presented at Appendix B. Recording Data Figure 3-7 Sample Units designated on the layout
sketch for inspection are located and identified on pavement by the team. The survey vehicle and a measuring wheel are normally used to locate designated Sample Units, and spray paint
is used to mark Sample Unit Boundaries. Layout Procedure Sample Unit MarkingsFigure 3-8 Figure 3-9 3-14 
__ 􀁾______________􀁾___NN _____________􀁾􀁾􀁾_____ 􀁾______________________ 􀁾􀁾􀀠Airport Pavement Inspection by PCI A high degree of precision is not required for layout of Sample
Units. Required standards are presented in Table 3-2. TABLE 3-2 Site Layout Standards Distance Tolerance (in feet) (in feet) 100 1 1,000 5 10,000 10 Inspectors add Feature boundaries
and modify Sample Unit configuration where necessary. If site dimensions are at variance with the layout sketch, the inspector establishing control makes appropriate adjustments. The
inspector must not, however, delete Feature boundaries from a sketch. Features are often outlined from pavement which has been overlayed by a subsequent project. Inspectors must be alert
to notice changes in pavement appearance or condition on the airport. Where traffic, poor drainage or other phenomenon has caused a section of pavement to deteriorate more rapidly than
surrounding pavement, that condition must be recognized. If the area is significantly larger than a single Sample Unit, a new Feature should be established. If the area can be contained
within, or be fairly represented by a single Sample Unit, it should be inspected as an Additional Sample Unit. If the abnormal condition exists on less than one quarter of a Sample Unit
area, it will not have a significant impact, and should be recorded as part of the distress pattern for the Sample Unit. The confidence level of sampling is enhanced significantly by
this procedure. Inspectors have to work in a variety of weather conditions including extremes of heat and cold and rain. Protection from the elements is an important responsibility of
each inspector, and especially the Team Chief. Proper clothing is essential. Figure 3-10 3-15 
____ _______________ _________ ________ ________________ ________ _ 􀁾􀀠􀁎􀁾􀀠􀁾􀁎􀀠􀁾􀀠􀁾􀁾􀀠Airport Pavement Inspection by PCl All inspectors must be carefully oriented to what we
call "airside etiquette". When they are on an airport, they must monitor the appropriate airport UNlCOM frequency. They must be familiar with traffic patterns and the importance of wind
direction to traffic flow. They must not leave equipment unattended on air traffic surfaces, and when they clear a runway for departing or landing aircraft, they must clear to a distance
equal to the holding line offsets. Aircraft traffic should never be disrupted at uncontrolled fields. Waiting For Traffic To Clear the Runway Figure 3-11 pilots preoccupied with landing
procedures may not notice a single person or small vehicle on the runway. The inspector must be alert to presence of air traffic. Runway As Seen From Final Approach Figure 3-12 3-16

__________ N _____ N __􀁾___ N ___􀁾____________ N ____________________________Airport Pavement Inspection by PCI Inspectors must respond immediately to Controller instructions at controlled
airports, and they must comply with one absolute rule. Aircraft ALWAYS have the right-of-way. Not all potential hazards are associated with air traffic. Working around motorized equipment
offers ample opportunity for the unwary to be injured. WATCH YOUR HEAD I I Figure 3-13 Detailed instructions for identification of distress types and severity, and for measuring distresses
are given in Chapter 5. 3-17 
􀁾􀁎􀁎􀁎______N ___ 􀁾__________________􀁾_______N ____________ _______________Airport Pavement Inspection by PCI CHAPTER Lf PAVEMENT CHARACTERISTICS WHAT IS PAVEMENT Pavement provides an all weather surface for wheeled vehicles and
it distributes wheel loads to subgrade. This function of distributing loads is not widely understood outside the engineering profession, but it is of vital importance in the study of
pavement characteristics. Chapter 2 of AC 150/5380-6, provides an excellent review of the load distribution function of rigid and flexible pavements, along with a discussion of their
composition and structure. Theoretically, virtually any material which can perform the two functions outlined above can be pavement. In fact, many materials have been used, including
stones, wood, metal plates and various other materials and mixtures. An ideal pavement would be strong, smooth yet with an excellent surface for braking, durable, attractive and inexpensive.
Nearly all pavement types offer some of these virtues, but so far, none are ideal. The best material or mixture is one which gives the greatest combination of these virtues. Modern highways
and airports are paved with the best materials we can provide in sufficient quantities at acceptable cost. Materials and mixtures vary widely as functions of climate, cost, availability
and choice, but to most of us, pavement can be broadly subdivided into two types classified as rigid and flexible. The most common ingredients are stone and a product to bind the stones
together. TYPES OF PAVEMENT Rigid pavements are usually bound with Portland cement, a by-product of limestone, which reacts with water to 4-1 
Airport Pavement Inspection by PCI􀁟􀁎􀁾􀁎􀁾􀁟􀁎􀁾􀁎􀁾􀁎___ 􀁾􀁾􀁾􀁎􀁾􀁟􀁎􀁾􀁎􀁟􀁾_____ 􀁾__􀁎􀁎􀁟􀁎􀁾􀁎􀁾􀁎􀁎􀁟􀁎􀁾􀁎􀁾_____N_ N ________ 􀁾􀁟􀁾___ produce a very hard rock-like substance
called concrete. Flexible pavements are usually bound with asphalt cement, a petroleum by-product with very low viscosity, or flow rate, at atmospheric temperatures. Portland cement
and asphalt cement have one very important characteristic in cornmon. Under mixing conditions, they are easily transported, placed and shaped, and in service they are stable and durable.
As has been mentioned, load distribution is a vital function of pavement. Both rigid and flexible pavements perform this function, but in very different ways. Rigid pavement distributes
loads by its internal ability to resist bending, called flexural strength. It acts as a bridge, and imposed wheel loads are distributed uniformly to subgrade from within the slab. Flexible
pavement distributes loads through layers of materials designed to resist compression. The result is the same, but the process is very different, and evidence of failure is determined
by the process. PAVEMENT DETERIORATION Pavement begins to deteriorate from the moment it is placed. Deterioration is a very complex process accelerated by environmental factors and use.
Chemical and physical effects of sun, wind, water and changing temperatures work constantly to destroy pavement. Loading and surface abrasion from traffic further accelerate the process.
Materials and procedures are carefully selected by engineers to build pavements capable of resisting this process. Deterioration, then, is a function of environment, traffic, and materials/procedures
. ENVIRONMENTAL FACTORS Environmental factors include erosion and the effects of thermal and chemical reactions. Erosion is a physical result of wind, water and sunlight. Wind and water
cause abrasive action which wears, dislodges and carries away exposed materials. Erosion is accelerated by stresses created when confined water freezes and expands. Sunlight contains
ultraviolet rays which attack and destroy microscopic components of exposed pavement. Thermal changes cause 4-2 
_____H _____________________________________________􀁾___________ 􀁾􀁟􀁾􀁾__ Airport Pavement Inspection by PCI materials to expand and contract, setting up stresses) and movements which
lead to separation of pavement particles, and eventual disintegration of the structure. Chemical reactions take place between pavement materials and through outside influences which
change physical characteristics of components. Not all of these reactions are bad. For instance, Portland cement continues to hydrate, and therefore to gain strength, through most of
its useful life. And the "kneading" action of traffic on flexible pavement actually helps to preserve its vitality. However, most environmental reactions in pavement work against it.
Asphalt in flexible pavement oxidizes, causing hardening and loss of elasticity. Water and air in contact with material particles cause chemical reactions which change the physical characteristics
of the particles resulting in loss of pavement integrity. Foreign products such as fuel, alcohol, exhaust byproducts, and varied air and water pollutants tend to accelerate the process.
TRAFFIC FACTORS Traffic causes deterioration through wheel loads and by abrasion. Wheel loads cause pavement to yield, or flex. Even rigid pavement will flex slightly under load. Pavement
reacts in one of two ways to this flexing action. It recovers to its original position, called elastic motion, or it remains deformed, called plastic motion. Most flexing under loads
is elastic, and movement is very slight. Deterioration takes place when repeated flexing movement begins to loosen bond between particles. In time, more particles separate, an increment
of integrity is lost, the flexing increases and deterioration accelerates. Eventually, cracks appear at the surface. Plastic motion can result from a single heavy load or from repeated
loadings. It can begin with the first wheel load or it can result from fatigue caused by elastic motion. At any rate, plastic motion results in surface irregularities which, in time,
can be observed. Rigid pavement is very resistant to plastic deformation. Consequently, when its elastic limit is reached, rigid pavement will break, leaving clearly visible cracks at
the surface. 4-3 
􀁾􀁎􀁎􀁾__􀁾􀁎􀁎________􀁾􀁎_________􀁾________________________________________Airport Pavement Inspection by PCI Moving wheels also cause abrasive deterioration. High point loads can
actually crush stones in pavement. Turning and braking movements create high shear stresses which can dislodge and displace particles. Airplane propellers and jet engines create air
turbulence which has an abrasive effect on pavement. Engine exhaust gases can be very hot and, when combined with blast effects, can significantly damage a pavement surface. ENGINEERING
FACTORS A pavement can only be as durable as the materials and procedures used in its construction. Modern pavements are made from natural materials which vary considerably in quality.
Engineers take these variations into account during design, but even so, inferior materials are often used. The way in which materials are combined and placed is also very important
to durability. Improper procedures can reduce service life significantly. Inferior materials, defective defective design and improper construotion procedures oause pavement deterioration
whioh oan be observed in distresses visible on the surface. RESURFACING FACTORS Old pavements are often rehabilitated by overlayment. This is a very attraotive procedure because it 􀁾􀁳􀀠relatively
inexpensive and it "restores old pavement to serviceable condition". In faot, overlayment does not restore old pavement. It merely covers old pavement with new pavement. Overlays do
reinstate roadways and airport pavements to serviceable condition. Pavement irregularities are reduced or eliminated and new surfaoes are provided. A new wearing surface presents an
attractive appearanoe and may easily lead one to believe that the pavement has been restored. However, distresses, and many oauses of those distresses, still exist in the old pavement.
Unless they are carefully neutralized in design, they will affeot the overlay, contributing to premature deterioration. Craoks soon refleot to the surface. Surfaoe irregularities gradually
return beoause the 4-4 
I __NN ___􀁾􀁎____􀁾􀁎􀁎___NN ___NN __􀁾􀁾􀁎􀁎􀁾_________N __________________________Airport Pavement Inspection by PCI underlying cause was not corrected. and the new surface eventually
takes on the appearance and shape of its predecessor. Many surface distresses in overlayments reflect conditions inherited from the old pavement. \ EVALUATING PAVEMENT CONDITION As a
pavement structure begins to fail. evidence of that failure often shows up at the surface. Pavement distress is represented by cracks. deformations. material loss and changes in appearance.
These anomalies are called distresses and. to a trained analyst. they tell a great deal about the condition of the pavement. Our ability to judge pavement condition by distress analysis
is a function of how well we can predict the underlying cause of each distress. Every visible distress in pavement is a result of one or more of the factors identified above. Fortunately,
it is possible, in most cases, to associate a distress with an underlying cause. This is is the basic premise of the PCI concept. 4-5 
􀁾___􀁎􀁟􀁾􀁾􀁾__________________________􀁾______􀁾􀁾􀁾􀁾______􀁾_ _______________ _Airport Pavement Inspection by PCI CHAPT£R 5 DISTRESS IDENTIFICATION AND MEASUREMENT INTRODUCTION
The reason the PCI procedure for pavement evaluation has been so widely accepted is that it offers a method to objectively rate pavement condition. The procedure evolved from the combined
experience of many pavement engineers and has been shown, in prototype projects, to fairly and consistently represent their cOllective ratings of a wide variety of pavements. Advisory
Circular 150/5380-6 provides descriptions and photograph examples of 31 distresses used in the PCI procedure to represent pavement condition. They are listed alphabetically by pavement
type in Chapter 2. These descriptions and photographs are the foundation of objectivity of the Pavement Condition Index method of pavement condition survey. The strength of PCI depends
on consistent identification and measurement of pavement distresses in the field. Descriptions and and photographs developed by the Corps of Engineers seem, at first glance, to identify
all distress conditions clearly. However, in practice it is evident that considerable interpretation and judgment are required of inspectors to achieve a level of consistency necessary
for reliable forecasting. A basic knowledge of pavement characteristics (Chapter 4), and a thorough understanding of what each distress type represents, are essential. PCI inspection
is much like any other investigation or scientific research. The inspector must not accept an apparent condition until he is convinced of the reason for the condition. Some distresses
are easy to read. Others are not so obvious. The inspector has not successfully completed the survey until all distresses have been correctly identified, interpreted for severity, and
accurately measured and recorded. 
􀁟􀁾􀁾___􀁎􀁾􀁾_____􀁾􀁎􀁟􀁎____________􀁾__________ 􀁾______________􀁾􀁟􀁾________ 􀁾__Airport Pavement Inspection by PCI This chapter presents our performance standards for PCI survey.
In order to achieve these standards, we have formalized our interpretations of distress types, severities and measurement procedures. Integrity of our work is imperative. Therefore,
descriptions provided in AC 􀁬􀀵􀀰􀀯􀀵􀀳􀀸􀀰􀁾􀀶􀀠are strictly observed. Each distress is introduced herein by reproducing and underlining the Corps of Engineers description, presented
word for word from AC 150/5380-6. Additional criteria and measurement standards provided represent collective judgment of the authors. They were first published, in draft, in 1986, and
were tested on 36 airports in Wisconsin and 20 airports in Indiana. The first edition of this manual presented several refinements to the criteria and standards based on PCI inspection
experience on those airports. This second edition presents further refinements and additions based based on inspections at an additional 100 airports. Survey party chiefs who participated
in the field tests, and who have contributed to continuing improvement of descriptions and inspection techniques, are experienced inspectors who have worked with the authors on airport
surveys for more than three years and have attended our annual PCI training course at least four times. Performance standards were established following an extensive quality review process
consisting of duplicate inspections by the authors of selected sample units on many airports. The standards are achievable with 80 percent consistency when duplicate inspections are
made of any sample unit of pavement by inspectors trained and supervised by the authors. The most significant result of these standards is that repeatability of survey data can now be
focused at sample unit level. Our standards are based on distress identification and measurement, not PCI values. The corrected deduct curves used in PCI calculation can change a PCI
value for a sample unit of pavement by several points in response to a very small change in distress density. For instance, if only one distress on a sample unit registers a deduct value
exceeding five points, the total deduct is equal to the sum of deduct values, say 40, and the PCI = 60. However, if a second distress type, by incremental increase, becomes a "greater
than five point" distress, the total deduct would be increased by only one point, but the resulting corrected deduct value would be 26. Unless the deduct value for a single distress
exceeded 26, the apparent change in PCI would be 14 points. 5-2 
___􀁾􀁾􀁎__ 􀁾􀁟􀁾􀁎􀁎􀁎􀁎􀁾􀁾􀁾􀁎􀁎__􀁾􀁾􀁎􀁾􀁎􀁎􀁾___􀁎􀁎􀁎􀁾􀁾􀁾􀁾____ 􀁾______________􀁾__N ________Airport Pavement Inspection by PCI This is an extreme example of the fallibility
of PCI computation, and such variations tend to "damp out" at feature level, but it is obvious that standards based on PCI values, as a determinant of data collection consistency, is
pointless. That is why we have developed the following performance standards for PCI inspections on airports. PERFORMANCE STANDARDS Certified PCI inspectors are expected to consistently
achieve inspection results on any designated sample unit within the following tolerances: Distress Type Identification. No variance. Severity Identification. One variance in three. Measurement.
(Sum of units of multiple severity distresses.) Linear 10 percent variance. Area (except patches) -20 percent variance. Patches 5 percent variance. IDENTIFICATION AND MEASUREMENT STANDARDS
Flexible Pavement. General Comments. 1. Record alligator cracking and rutting independently. These distresses are caused by loads and often exist together in the same pavement area,
but with different densities. 2. Bleeding and polished aggregate are distresses which represent loss of friction properties on a pavement surface. When both occur on the same pavement,
record only bleeding. 3. Block cracking is an advanced form of longitudinal/5-3 
__________N ___________________________________________________________Airport Pavement Inspection by PCI transverse cracking. Block cracking is measured by area and incorporates all
longitudinal/transverse cracking within that area. 4. Cracking reflected from an underlying rigid pavement has different origins than block cracking, and is recorded separately when
found on the same pavement. Reflection cracks from pavement joints are recorded as Joint Reflection Cracks, and reflection cracks from cracks in underlying pavement are recorded as LOngitudinal
and Transverse Cracks. 5. Measurements of differential elevation for severity determination of area distress types are made under a ten foot straight edge. Measurement of differential
elevation at cracks in flexible pavement, and for all distress types in rigid pavement, is made under a straight edge of one foot length. 6. A ten foot long by 3/4 inch 1.0. water pipe
makes a good straight edge. Check the straightedge frequently by sighting through the pipe or by rolling it slowly along the pavement. 7. Distresses located within one foot of a pavement
edge adjacent to an unstabilized shoulder are ignored in the survey. These distresses are normally caused by weak subgrade conditions at edge of pavement. Cracks at pavement edge are
recorded in street/highway surveys, but no defined distress type is provided for airport surveys. The reason is that runway and taxiway pavement are wide enough that the outer edges
are not critical to serviceability. 8. 1/8 inch is the smallest measureable dimension in identifying area boundaries and in establishing distress severity. 9. Structures in pavement,
and designed pavement geometry, are not used to measure for determination of distress severity and area. 10. Surface treatments are not structural components of a pavement structure.
They protect the pavement in much the same way that paint protects wood. They tend to obscure distress conditions at the pavement surface. To the extent possible, it is important to
"read through" a seal coat and rate the underlying distress types and severities. 11. A PCI survey provides a record of the condition of pavement at an instant in time. Record what you
􀁾􀀬􀀠not what you believe, or think will be. 􀀬􀁾􀀬􀀠,; 5-4 
__NNNNNN _____ NNN_N ____________________________________________􀁾______ _Airport Pavement Inspection by PCI 12. 13. 14. pavement in excellent condition can be fairly represented with
a reduced sampling rate. When authorized by the owner, pavement with PCI above 90 may be inspected at a 10 percent sampling rate. This requires that all inspected sample units have PCI
above 90. Inspectors must visually confirm that inspected sample units are, in fact, representative of the pavement. Pavement in advanced stages of deterioration is very difficult to
inspect quantitatively. Time required to measure multiple distress types at various levels of severity is not justified on pavement which is obviously in failed condition. When authorized
by the Owner, pavement with PCI below 40 may be inspected at a 10 percent sampling rate. This requires that all inspected sample units have PCI less than 40. Inspectors must visually
confirm that inspected sample units are, in fact, representative of the pavement. When authorized by the Owner, inspection may be terminated in a sample unit when any distress listed
at Table 5-1 exceeds the density shown. Distresses indicate failed pavement correctable only by reconstruction or overlay. Density values correspond to deducts of 60 points or more,
assuring PCI less than 40. TABLE 5-1 Maximum Distress Density Distress 􀁾􀀠Severity Density (%) Alligator Cracking Medium High 20 10 Block Cracking High 50 Corrugation Medium High 20
10 Depression Medium High 50 20 Rutting Medium High 50 10 Slippage Cracking 20 Swell Medium High 50 20 5-5 
___ _ 􀀧􀁟􀁎􀁎􀁟􀁎􀁾􀁎______N _____􀁾___________________􀁾_______􀁾􀀠Airport Pavement Inspection by PCI Cracking Distress. The most common distress type encountered in PCI inspection
is cracking. Criteria for determining crack severity is the same for all distress types based on cracking. Therefore, standards for crack severity are presented below. These standards
apply for block, reflective, and longitudinal/transverse cracking distress types, and for evaluating severity of alligator cracks and patches. Standard Text. a. Low severity level (L).
Cracks have either littre-or no spalling with no loose particles. The cracks can--be filled--or :nonfilled. Nonfilled cracks have a mean width of 1/4 in. or less. Filled cracks are of
any width, but 􀁾􀁥􀁩􀁲􀀭􀁦􀁩􀁬􀁬􀁥􀁲􀀠material is in-satISfactory conditIOn. Additional Criteria 1. Filler is in satisfactory condition if it prevents water from entering the crack
and if it is pliable. Both conditions are necessary. It is not uncommon for filler to completely obscure obscure a low severity crack from view for a short distance. On the other hand,
filler is often "dribbled" on pavement where there is no crack. Try to establish whether a crack actually exists under filler material, but, when in doubt, record as low severity cracking.
Water access is evidenced if a knife blade can be inserted between filler and either crack face without meeting resistance. Water access may be evident by visual examination. Growing
vegetation in a crack is evidence of unsatisfactory filler, but do not be fooled by mower clippings in the crack. Sand in a crack is not evidence of unsatisfactory filler. If sand is
present, it must be removed to expose filler before a determination can be made. Depth of filler below pavement surface is not a factor in determining filler condition. 2. Spalling is
represented by loss of material at the crack face. Spalling results from pavement particles (of one square inch or larger surface 5-6 
__ 􀁾􀁟􀁾􀁾_________ 􀁾􀁟􀁎______􀁾__________􀁾􀁾_________ 􀁾_______ _______________NAirport Pavement Inspection by PCI area) breaking away from the surface due to impact of traffic
loads or by compressive forces within the pavement. A frayed edge (as if rounded by sandpaper) does not constitute a spalled crack. Little, light or minor spalling means no spalled particles
are larger than four square inches, and less than ten percent of the crack face is spalled. 3. Mean width is the predominant width in anyone foot crack segment. Severity is rated foot
by foot along the crack length, except spalls less than one foot long are considered incidental. Standard Text. b. Medium severity level (M) • One of the following conditions exists.--(1)
Cracks are moderately spalled with few IOOse particles-and can be either fITTed or nonfilled of any width. (2) Filled cracks are not spalled or 􀁾only IIghtly spalled, 􀁢􀁵􀁴􀁾􀁨􀁥􀀭􀁦􀁩􀁬􀁬􀁥􀁲􀀠is
in unsatisfactory condition-.-(3) Nonfilled cracks are not spalled or only TIghtly spalled, but---mean crack width is greater than 1/4 inch. (4) Light random cracking exists near the
crack 􀁾at the corners of 􀁩􀁮􀁴􀁥􀁲􀁳􀁥􀁣􀁴􀁩􀁮􀁧􀀭􀁣􀁲􀁡􀁣􀁾􀀠Additional Criteria 1. Filled cracks with unsatisfactory filler are subject to width criteria described above. If 1/4
inch wide or less, and meeting spall criteria, a crack with unsatisfactory filler is rated at low severity. Pavement condition is not reduced by Owner maintenance. Cracks wider than
3 inches are rated at high severity. Three inches is the maximum trench width allowed on airport traffic surfaces for safe operations. If there is evidence of measurable (1/8") subsidence
of pavement edges into the void at a crack face, record the crack at medium severity. 5-7 
􀁎􀁟􀁾􀁾􀁎􀁟􀁎􀁟􀁎􀁟􀁎__N ____N _______________________􀁾___________________________Airport Pavement Inspection by PCI 2. When a small piece of pavement with one face at a crack separates
full depth of the surface course, the separation is a result of secondary cracking which isolates the small piece from the pavement mass. The isolated piece may range in size from a
fist-size chunk, to a long thin strip adjacent to the crack. This condition is aggravated by traffic loads and/or loss of subgrade support. As this oondition deteriorates, the associated
crack is rated accordingly. The following definitions are oonsistent with standard criteria whioh describe such separations as moderate spalling. Spalling may be evident over the entire
length of the crack. Spall ohunks may be of any size but must be securely attached to the pavement. Isolated chunks smaller than 25 square inches in surface area may be loose in plaoe,
but not missing. Loose pieces may not represent potential voids in pavement wider than three inches in smallest dimension. Isolated partioles means along less than ten percent of the
craok length. A light random craok outlines a moderate spall in an early stage of development. Standard Text. o. ¥i9h severity level (H). Cracks are severely spal ed with loose and mISSIng
particliS7 They 􀁾􀀠be either filled or nonfilled of any width. Additional Criteria 1. Severe spalling is any degree of spalling exoeeding oriteria outlined above. 2. A spall may be
rated severe due to subsidenoe of assooiated pavement partioles into the oraok void. This condition can exist even though seoonddary cracking may not be visible. Record a orack at high
severity if subsidence associated with the crack exceeds 1/2 inch. 5-8 
􀁾􀀠􀁾􀁾􀀠􀁾 _______________________________________ __N ______ _______ ___________Airport Pavement Inspection by PCI NO DISTRESS Edge cracking Good Butt Joint Figure 5-1 Figure 5-2
LOW SEVERITY CRACKS paving Butt Joint Joint Reflection Crack Figure 5-3 Figure 5-4 Figure 5-3 is a low severity crack close in, closes to a good butt joint at center, then reappears
at medium severity due to moderate spalling near the top. Figure 5-4 is a low severity crack with frayed edges. The spalled area at the bottom is incidental (less than 10 percent of
the crack length.) 5-9 
􀁟􀁾􀁎􀁾􀁎􀁾__ 􀁾__ N __􀁎􀁾􀁎__ 􀁎􀁟􀁎􀁾􀁎___􀁾􀁎􀁟􀁎_____􀁾__ N _____________ 􀁾________􀁾__ 􀁾___ _Airport pavement Inspection by PCI , LOW SEVERITY CRACKS Figure 5-5 Figure 5-6 At
Figure 5-5, sealer stops, but the crack continues. Measure the crack, not the sealer. At Figure 5-6, Sealer is in satisfactory condition. Low Severity Crack Medium Severity Crack Figure
5-7 Figure 5-8 Sealer in crack at Figure 5-7 is more than one inch below the surface, but is it in satisfactory condition. Sealer in crack at Figure 5-8 is also satisfactory, but the
crack is moderately spalled. 5-10 
____􀁾___ N ______ 􀁾_________________________ N __________ N __􀁾_____________ _Airport Pavement Inspection by PCI MEDIUM SEVERITY CRACKS wi SPALLS Figure 5-9 Figure 5-10 Crack at Figure
5-9 is moderately spalled. Crack at Figure 5-10 is wider than 1/4 inch. Spall in Figure 5-10 is incidental, but is considered "loose" since aggregate interlock at the face is lost. MEDIUM
SEVERITY CRACKS wiSECONDARY CRACKING Figure 5-11 Figure 5-12 Crack at Figure 5-11 is rated at medium severity due to secondary cracking. Note that secondary cracks are within 6 inches
of the primary crack. Figure 5-12 shows a crack at medium severity, wider than 1/4 inch, with secondary cracking close in. Secondary cracks develop into severe spalls (aggregate interlock
lost and wider than 3 inch void potential) at top of picture, changing severity to high. 5-11 
􀁾􀁟􀁾___________ 􀁾􀁟􀁎___􀁾􀁟􀁾__________􀁾􀁟􀁾􀁟􀁾_______􀁾_____􀁾_________________􀁾􀀠Airport Pavement Inspection by PCI MEDIUM SEVERITY CRACKS w/SUBSIDENCE Figure 5-13 Figure 5-14
Subsidence is measurable (1/8"), but less than 1/2 inch, and is localized within 6 inches of the crack. If measurable subsidence exists beyond 6 inches from the crack, measure and record
"depression" (in absence of secondary cracks or spalls) or "rutting" (if secondary cracking or spalling are present). HIGH SEVERITY CRACKS w/SUBSIDENCE Figure 5-15 Figure 5-16 Subsidence
at pavement edge (be careful not to measure into the crack) is at 1/2 inch or more. 5-12 
__ 􀁎􀁾􀁎􀁾􀁟􀁾􀁾􀁾􀁎􀁎􀁟􀁾􀁟􀁎􀁎􀁎􀁎_____􀁾_________________________N ___ ______ 􀁾________ _Airport Pavement Inspection by PCI HIGH SEVERITY CRACKS w/SPALLING Figure 5-17 Figure 5-18
The joint reflection crack at Figure 5-17 is severely spalled close in with missing pieces. Near the top, the crack changes to low severity. Figure 5-18 shows a severely spalled crack
with loose pieces (aggregate interlock lost) over virtualy the full length. HIGH SEVERITY CRACK Figure 5-19 Although the sealer in this crack is in satisfactory condition, crack width
measures in excess of 3 inches. Before rating a crack at high severity for width, be sure to locate, and measure between, vertical faces of the crack with a knife blade. Sealer may be
misleading. 5-13 
__􀁎􀁾􀁾􀁟􀁾___􀁾____􀁾__􀁾______________________􀁾__ 􀁾___ 􀁾􀁾___􀁾􀁟􀁾______________Airport Pavement Inspection by PCI 1. 2. 3. 4. 5. Measuring Techniques. Measuring linear units
of distress is usually quite straight forward. Use of a calibrated wheel distance measuring device is the most cornman procedure. When longitudinal crack patterns are limited to paving
lane joints and transverse cracks extend across the pavement, experienced inspectors can Calibrated Wheel accurately estimate quan-Figure 5-20 tities by multiplying the number of longitudinal
and transverse cracks by length and width of sample unit, respectively. This technique must never be attempted in sample units with complex crack patterns, or until accuracy can be clearly
demonstrated by duplicating measurements with a calibrated wheel. Inspectors should cross check each other's work frequently when this procedureis being used. If published standards are not met consistently, the calibrated wheel must be used. Measuring joint reflection cracks and longitudinal and transverse cracks can be difficult.
There is a tendency to lose track of the Sample Unit boundary. This difficulty will diminish with experience. Where there is a large amount of cracking, it is easy to get "lost" in the
Sample Unit, forgetting which cracks have been measured. overcoming this difficulty requires subdividing the sample unit into clearly definable segments. If paving lane joints are visible,
cracks can be measured one lane at a time. Occasionally, prominent transverse cracks can be used for reference. If no visible references are available, it may be necessary to mark segment
corners with paint or crayon. It is, however, imperative to maintain positive points of reference in the sample unit. Keeping track of different crack severities while measuring can
also be difficult. If most of the cracking is of one severity with just a minor amount of another severity, it may be possible to measure the total, keeping track of the minor quantity
mentally. In most cases, however, however, it will 5-14 
􀁾􀁾􀁾___􀁾􀁾􀁎____NNN __N ___________ NN _________􀁾__________􀁾_ _ 􀁾􀁾____________ _Airport Pavement Inspection by PCI 6. 7. 8. 9. 10. be necessary to measure each severity separately,
marking transitions with spray paint or crayon. It is best to measure alligator and block cracking first. With these areas marked, the remaining sample unit area will be smaller. Then
subdivide the sample unit into segments, and measure the remaining cracks as described above. Small areas of distress can be estimated by visualizing a rectangular area of equivalent
size, and calculating the area of the rectangle. When an area is large or of irregular shape, it is necessary to physically mark boundaries on the pavement. A lumber marking crayon or
spray paint is recommended for this purpose. As limits of an area are identified, small marks are made with crayon to define the boundaries. Boundaries of multiple Marking Area Boundary
severities of a distress Figure 5-21 are outlined in the same manner. When the area has been defined by intermittent crayon marks, measuring proceeds as described above. When multiple
severities of a distress exist in the same area, each severity must be isolated and measured. The most common technique is to define and measure the entire area and then define and measure
the least extensive severity of distress within the overall area. Where three severities are involved,the process is repeated, measuring severity of least area, then severity of next
greater area, and subtracting each, in turn, from the next. All distress types, except jOint reflection and longitudinal and transverse cracking, require area measurements. Techniques
for obtaining area measurements of various distresses are presented here. a. Area boundaries of Alligator Cracking are defined at 6 inches beyond the outermost visible crack in the pattern.
When a single crack is visible, width is one foot. Area boundaries should be marked intermittently with crayon or paint. 5-15 
__􀁾___ 􀁾__________________􀁎􀁎􀁾__􀁾􀁟􀁾______ 􀁾____􀁾_________􀁾______________ 􀁾􀀠Airport Pavement Inspection by PCI b. Area boundaries of Bleeding are defined at 25 percent coverage
of pavement surface. ) c. Area boundaries of Block Cracking a£" dafilIed &􀁦􀁥􀁥􀁾􀀠beyoRd the outermost crack in the pattern. d. Area boundaries of Jet Blast Erosion, Oil Spillage,
patching, Polished Aggregate, Raveling and Weathering, and Slippage Cracking are defined at the outer edges of visible distress. e. Area boundaries of other distress types are defined
where minimum measurable (l/8") differential elevation is reached. 11. Measuring width of cracks, depth of depressions and rutting, and height of swells can be expedited by calibrating
tools and equipment on hand to the key dimensions, which are 1/8", 1/4", 1/2", 1" and 3". For example, a clip board may be 1/8" thick, a pencil may be 1/4" thick, etc. Fingers can be
calibrated to close tolerance. A pocket knife can be an excellent measuring device in addition to its value in examining crack filler and condition of pavement surface. Examples of efficient
measuring techniques are shown below. Measuring 1/8 Inch Measuring 1/2 Inch Figure 5-22 Figure 5-23 5-16 
___ 􀁾____________________________ N ____________________􀁾________ 􀁾______ _Airport Pavement Inspection by PCI 12. With practice, the 3/4 inch cast pipe straight edge can be maneuvered
quite efficiently with a foot, as demonstrated below. Rolling Forward Sliding Laterally Figure 5-24 Figure 5-25 5· 
_______N ___ 􀁾__􀁾􀁟􀁾______ 􀁾____􀁾􀁟􀁾______________________________________Airport Pavement Inspection by PCI ALLIGATOR OR FATIGUE CRACKING -DISTRESS NO.1. ..'" j Standard Text.
Description. 􀁾􀀠Alligator 􀁾􀀠fatigue cracking is 􀁾􀀠series of interconnecting cracks caused by fatigue failure of the asphaltic concrete (AC) surface under repeated traffic loading.
The cracking initiates at the bottom of the AC surface (or stabilized baser-where tensile-Stress and strain are highest under 􀁾􀀠wheel load. The cracks propagate to the surface initially
as 􀁾􀀠series of parallel cracks. After repeated traffic loading, the cracks connect, forming many-sided, sharp-angled pieces that develop 􀁾􀀠pattern resembling chicken wire or the
skin of 􀁾alligator. The pieces are less than 􀁾􀀠ft 􀁾the longest side. 􀁾􀀠Alligator cracking occurs only 􀁾areas 􀁾􀀠are subjected to repeated traffic 􀁬􀁯􀁡􀁤􀁾􀁮􀁧􀁳􀀬􀀠such 􀁾􀀠wheel
paths. Therefore, it would not occur over an entire 􀁾unless the entire area was subjected to traffic loading. Pattern type cracking, which occurs 􀁾􀁾􀀠entire 􀁾that is 􀁾subjected
to loading, is rated as block cracking, which is 􀁾􀁾􀀠load-associated distress. Severity Levels. a. Low severity level (L). Fine, longitudinal hairIIne cracks running parallel to one
another with none or only 􀁾􀀠few interconnecting-cracks. The cracks are 􀁾spalled. b. Medium severity level (M). Further development of light alligator crackrng-into 􀁾􀀠pattern or
network of cracks 􀁾may be lightly spalled. 􀁾􀀠High severity level (H). Network 􀁾􀀠pattern cracking has progressed so that the pieces are well defined and spalled at the edges; some
of the pieces rock under traffic. Measuring Procedure. Alligator cracking is measured in square feet of surface area. The major diffICulty in measuring this type of distress is that
many times 􀁾􀁾􀀠three levels of severity exist within one distressed area. If these portions can be easily distinguished from one another, they shOuld be 5-18 
􀁾􀁾􀁾_____ 􀁾__________NN _________ 􀁾____________ 􀁾􀁾___________________ 􀁾____Airport Pavement Inspection by PCI measured and recorded separately. However, if the different-rBvels
of severity cannot be easIlY divided, the entire area should be rated at the highest severity levey-present. Additional Criteria 1. Alligator cracking can have a circular or linear pattern.
On thicker pavement sections, cracks may appear random rather than linear or circular. 2. Alligator cracking may initially appear in wheel tracks as linear parallel cracks when associated
with rutting. 3. Pavement overloads on weak subgrade by rollers during construction can cause alligator cracking of new pavement. These cracks must be distinguished from blemishes caused
by tearing of pavement surface by rollers sliding on, or pushing, the hot mix. Alligator cracks extend through the pavement surface course. 4. Some surface treatments, and paint, develop
surface blemishes with linear or rectangular patterns similar in appearance to alligator cracks. Usually, the distinction will be obvious to a trained inspector. When in doubt, check
the depth of crack. Surface blemishes do not extend into the pavement more than about 1/4 to 1/2 inch. Alligator cracking extends through the surface course. 5. A single crack may be
load related, and therefore, an alligator crack. When identified as such, single alligator cracks are measured by length times one foot. 6. Cracks which define blocks larger than 2 feet
on a side are not Alligator Cracks. Measure and Record L & T CraCking. 7. Establishing between severities of this distress type may be difficult, especially since multiple severities
are common in a single distressed area. Two factors help to identify low severity alligator cracks. Cal There is no pattern of interconnecting cracks, although there may be an occasional
random crack connecting two parallel cracks. (b) The individual cracks rate at low severity as defined elsewhere in this Chapter. Medium severity alligator cracking is defined by 5-19

, ________ NN ____􀁾____ 􀁾___ 􀁾􀁎____ 􀁎􀁾__N __________________Airport Pavement Inspection by PCI (a) a well defined pattern of interconnecting cracks, (b) the block pattern is generally
rectangular, (c) all pieces are securely held in place (good aggregate interlock between pieces). High severity alligator cracks are identified by (a) blocks which are approximately
equally sided, 􀁡􀁮􀁾􀁳􀁭􀁡􀁬􀁬􀁥􀁲􀀠than 6 inches on a side, (b) individual 􀁾􀁡􀁣􀁫􀁳􀀠rate at medium or high severity, (c) individu pieces are missing or loose in place (aggte interlock
lost). Loose or missing pieces a positive indication of high severity alligator cracking. 8. In areas of multiple severities, isolate areas by severity and measure each separately. Areas
smaller than five square feet may be included with adjacent distressed areas. 9. For purposes of area definition, intermittent crack segments may be considered continuous if gaps do
not exceed 20 percent of the total crack length. This provision is not to be used in determining distress severity. 10. Any uncertainty about severity defaults to the higher severity.
11. The following photographs illustrate alligator cracking criteria. NO DISTRESS Figure 5-26 Figure 5-27 Paint and tar based surface treatments have different thermal properties than
asphalt. Consequently, they develop surface craCKS similar to the alligator pattern. Figures 5-26 and 5027 illustrate such cracks, known as blemishes. They are not distresses. 5-20 
􀁎􀁟􀁾__􀁾____􀁎􀁾􀁎_____N _______􀁾______________ 􀁾___􀁾􀁟􀁎__________􀁾􀀠_____ 􀁾___NAirport Pavement Inspection by PCI NO DISTRESS Figure 5-28 Figure 5-29 Figure 5-28 shows pavement
grooved for better drainage to prevent hydroplaning. Figure 5-29 shows a roller mark simulating alligator cracking. However, these cracks do not extend full depth of pavement, except
for one short crack at the center of the photo which is too small to be significant. LOW SEVERITY ALLIGATOR CRACKING Figure 5-30 Figure 5-31 Roller marks at Figure 5-30 extend through
the pavement and meet low severity criteria. Secondary cracks at Figure 5-31 extend more than 6 inches from the primary crack and are measured as low severity alligator cracking. The
primary crack is included in the area measurement and is not measured separately. 5-21 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭LOW SEVERITY
ALLIGATOR CRACKING Figure 5-32 Figure 5-33 Cracks in Figure 5-33 are well defined. but lateral cracks are more than two feet apart. LOW SEVERITY ALLIGATOR CRACKING Figure 5-34 Figure
5-35 Cracks at Figure 5-34 are approaching medium severity. Lateral cracks are beginning to form a pattern. Cracks at Figure 5-35 result from a soft spot in subgrade. 5-22 
___􀁾􀁟􀁎__NNNN ____N __􀁾________________􀁾____􀁾_____􀁾􀁎__ 􀁾_______ 􀁾________ _Airport Pavement Inspection by PCI LOW SEVERITY ALLIGATOR CRACKING Figure 5-36 Figure 5-37 Cracks
at Figure 5-36 might be rated as longitudinal except for the traffic lane indicated by wheel marks. Crack at Figure 5-37 results from a localized weakness within the pavement structure.
It is characterized by a random pattern seemingly from nowhere and going nowhere. The crack often takes the shape of a tree branch and the origin of the crack is at the fork. Single
cracks are measured by length times one foot. Closeup of "Tree Branch" Alligator Crack Figure 5-38 5-23 
􀁾􀀠􀁾 N _________________ N _______________ ______________________________ __ _ Airport Pavement Inspection by PCI \ MEDIUM SEVERITY ALLIGATOR CRACK Figure 5-39 Figure 5-40 Figures
5-39 and 5-40 present classic alligator cracking at medium severity. Pattern is well established and rectangular in shape, and pieces are firmly secure in place (good aggregate interlock).
MEDIUM SEVERITY ALLIGATOR CRACKING Figure 5-41 Figure 5-41 shows classic medium severity alligator cracking in a circular pattern. 5-24 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭I \ I MEDIUM
SEVERITY ALLIGATOR CRACKING Figure 5-42 Figure 5-43 Crack patterns are often obscured by dirt and debris, making identification more difficult. Crack pattern and severity must be determined
before a rating is assessed. MEDIUM SEVERITY ALLIGATOR CRACKING Figure 5-44 Figure 5-45 Alligator cracking is common near cracks where moisture softens subgrade, weakening pavement support.
Figures 5-44 and 5-45 are examples. In Figure 5-45, the primary crack defines high severity alligator cracking one foot wide. Adjacent cracks are at medium severity. Cracks further out
are measured as transverse cracks, since they define pieces larger than two feet on a side. 5-25 
􀁟􀁾􀁈____________􀁾__􀁾__􀁾________􀁾__ 􀁾_____􀁾________􀁾_________ 􀁾􀁟􀁾__ 􀁾_____Airport Pavement Inspection by PCI ..􀁾􀀠LONGITUDINAL AND TRANSVERSE CRACKING (L & T) Figure 5-46
Cracks at Figure 5-46 resemble alligator cracking except that they define pavement pieces larger than two feet on a side. Pieces this large provide considerable bearing strength and
defining cracks are rated as L & T. HIGH SEVERITY ALLIGATOR CRACKS Figure 5-47 Figure 5-48 These figures present classic high severity alligator cracking patterns. Individual pieces
are small and nearly square, aggregate interlock is lost, and bearing strength of pavement is virtually lost. Figure 5-47 shows a small amount of missing pieces, and is actually the
more severe. Cracks at Figure 5-48 appear more severe because they are wet. Rating on wet pavement must be done with special care. 5-26 
Airport Pavement Inspection by PCI 􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭HIGH SEVERITY
ALLIGATOR CRACKING Figure 5-49 Figure 5-50 These photos represent alligator cracking in most advanced stages. The patch in Figure 5-49 is ignored, as the original distress is more serious.
The pothole at Figure 5-50 is the ultimate alligator crack pattern. ALLIGATOR CRACKS IN WHEEL TRACKS Figure 5-51 Figure 5-51 shows a classic pattern of alligator cracking in wheel tracks
on a taxiway. They are not centered because the taxiway was recently widened, shifting centerline to the right. 5-27 
􀁾􀁎􀁎􀁾􀁎____􀁾________ 􀁾􀁟􀁾_______ 􀁾􀀠___________ 􀁾__ 􀁾􀁟􀁎________ _______________Airport Pavement Inspection by PCI BLEEDING -DISTRESS NO.2. Standard Text. Description. Bleeding
is a film of bituminous material on the pavement surface that creates 􀁾􀀠shiny, glass-rike; reflecting surface that usually becomes quite sticky. Bleeding is caused 􀁾excessive amounts
of asphaltic cement or 􀁾in the mix and/or low air void content. It occurs when asphalt fills the voids of the mix during hot weather and then expandS-out onto the surface of the pavement.
Since the bleeding process is not-reversible during cold weather, asphalt or 􀁾will accumulate on the Silrf"ace. Severity Levels. 􀁾degrees of severity are defined. Bleeding should be
noted when it is extensive enough to cause a-reduction in skia-resistance. Measuring Procedure. Bleeding is measured in square feet of surface area. Additional Criteria 1. Bleeding usually
appears as spots or "pools" of bitumen on the surface, but may be concentrated along a crack when permeating from a base layer since the crack offers least resistance. Bleeding associated
with cracks may be difficult to distinguish from crack filler. If the area is large enough to be recorded, it is almost certainly bleeding. 2. Fresh bleeding is shiny and sticky. However,
in a dormant condition, bitumen may be dull from oxidation, dust and pollutants. Fresh bitumen may be exposed using a knife blade. A knife blade can also help in distinguishing a dome
of bleeding bitumen from a coated aggregate particle. Bleeding may also be camouflaged by rubber deposits from tires of landing aircraft. Bleeding bitumen under rubber deposits may be
very difficult to detect. Use a knife blade to expose the body of material. Fresh bitumen is shiny and will stick to the knife blade. 5-28 
1 __ NNN ____􀁎􀁎􀁎􀁎􀁟􀁾__NNN ____NN ___􀁾􀁾􀁎􀁎__ 􀁾􀀠___N ________􀁎􀁾_______􀁾􀁾􀁎______􀁾􀁾􀁟Airport Pavement Inspection by PCI 3. If boundaries of the distressed area are not obvious,
locate a one square foot area approximately 25 percent covered by exposed bitumen. \ This area represents the appearance of pavement at the boundaries of the distressed area. 4. Distressed
areas smaller than 25 square feet are not recorded. BLEEDING Figure 5-52 Figure 5-53 Classic Bleeding pattern is shown at Figure 5-52. This photo shows the distress at about 50 percent
coverage. Figure 5-53 shows a Bleeding pattern at a paving lane construction joint. This is much less common, caused by excess bitumen in an underlying layer. 5-29 
.N __ N ___ N ______________________________________ 􀁾_____Airport Pavement Inspection by PCI BLOCK CRACKING -DISTRESS NO.3. Standard Text. Description. Block cracks are interconnected
cracks that divide the pavement into approximately rectangurar-pieces. The blocks may range in size from approximately ! by ! ft to 10 £x. 10 ft. When the blocks are larger than 10 £l
10 ft, they 􀁾classified as longitudinal or transverse cracking. Block cracking is caused mainly by shrinkage of the asphalt concrete and daily tem erature cycling-rwhich results in
daily stress strain cycling). It is not loadassociated. The occurrence of block cracking usually indicates 􀁾􀀠the asphalt has hardened significantly. Block cracking normally occurs
􀁾􀀠􀁾􀀠large portion of pavement area, but sometimes will occur only in nontraffic areas. This type of dIStress differs from alligator cracking in 􀁾􀀠the alligator cracks form smaller,
many-s1ded pieces with sharp angles. Also unlike block cracks, alligator cracks 􀁾caused by repeated traffic loadings and are, therefore, located only in traffic areas (i.e., wheel paths).
Severity Levels. (Severity levels Comments, item 9, are presented page 5-5). under General Measuring Procedure. Block cracking is measured in square surface area, and usually occurs
at one level in 􀁾􀀠given pavement section. --Any feet of severitY areas of the pavement section having distinctly different levels of severity, however, should be measured and recorded
separately. Additional Criteria 1. Size of block is not a factor in rating severity. Severity of the distress is the same as severity of the defining cracks. If crack severity changes
from one area of a sample unit to another, record both severities of block cracking. If crack severity changes within a pattern, record block cracking at the dominant severity (more
than 50 percent) • 5-30 
􀁾􀀠􀁾􀀠􀁾􀁾 _______ __ _____ N __________ N ______________________________ ___N ____ _Airport Pavement Inspection by PCI 2. Cracks caused by pavement construction joints are used in
establishing a block pattern, but reflection cracks from underlying rigid pavement are not included. This distinction is important in properly identifying, measuring and recording the
block cracking distress type. 3. Block cracking should not be recorded when crack separation exceeds ten feet. If in doubt, measure and record longitudinal/transverse cracking. 4. If
the block pattern is contained in an area smaller than 100 square feet, measure and record longitudinal/transverse cracking. 5. For visualization of block crack pattern, consider intermittent
cracks on line to be continuous if gaps do not exceed 20 percent of total crack length. 6. Where block cracking and longitudinal/transverse cracking are both identified in a Sample Unit,
measure block cracking first and outline areas of block cracking with paint or crayon. This will reduce potential for inadvertently measuring the same crack for both distress types.
BLOCK CRACKING Figure 5-54 Figure 5-55 5-31 
Airport Pavement Inspection by pcr 􀀭􀁾􀀭􀀭􀀭􀁾􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭BLOCK CRACKING
Figure 5-56 5-32 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭CORRUGATION
-DISTRESS NO.4. Standard Text. Description. Corrugation is 􀁾􀀠series of closely spaced ridges and valleys \ripples) occurring at fairly regular intervals (usually less than 􀁾􀀠ftl
along the pavement. The ridges are perpendicular to the traffic direction. Traffic action combined with an unstable pavement surface 􀁾􀀠base usually-causes this type of distress. Corrugation
is not commonly found on airport pavement. Severity Levels. a. Low severity level (L). Corrugations are minor and do not significantly-affect ride qualItY (see measurement criteria below).
b. Medium severity level (M). Corrugations are noticeable and significantly -affect ride qualItY (see measurement criteria below). c. High severity level (H). Corrugations are easily
noticed and severerx--affect ride quality (see measurement criteria below). Measuring Procedure. Corrugation is measured in square feet of surface area. The mean elevation-difference--between
the ridges and varIeys of the corrugations indicateS the level of severity. TO determine the 􀁾􀀠eIevation difference, 􀁾􀀠le-ft straightedge should be placed perpendicular to the corrugations
so that the depth of the valleys 􀁾be measured in inches. The mean depth is calculated from five such iii:e"asurernents. Runways and Taxiways and Severity High-Speed Taxiways Aprons
L <1/4 in. <1/2 in. M 1/4 ::. 1/2 in. 1/2 -1 in. H >1/2 in. >1 in. 5-33 
i # ___ N _____NN _____________N _______􀁾_____􀁾􀁎__NN________Airport Pavement Inspection by PCI Additional Criteria 1. Corrugations are caused by repeated braking of vehicles in a
concentrated area, as at a stop sign on a down grade. If corrugations occur on an airport surface, they are most likely, on taxiways, near holding lines and, on runways, approaching
exit taxiways. 2. More common distress types, which might be'.i mistaken for corrugations, are swell caused by ice crystals under paint stripes, and depressions caused by parked vehicles
which appear as "moguls" or waves in pavement. 3. Corrugations result from horizontal forces on the surface which exceed the ability of the pavement structure to resist movement. 5-34

􀁾􀁟􀁾􀁎􀁎___􀁾􀁟􀁾􀁾_____􀁾􀁟􀁎􀁎_______􀁾____ 􀁾______________􀁾􀁾___ 􀁾_______________Airport pavement Inspection by PCI DEPRESSION -DISTRESS NO.5. Standard Text. Description. Depressions
are localized pavement surface areas having elevatIOns slightly lower than those of the surrounding pavement. In many instances, -right depressions 􀁾􀀠not noticeable until after 􀁾􀀠rain,
when ponding water creates "birdbath" areas: but the depressions 􀁾also be located without rain because of stains created Ex pending of water. Depressions 􀁾􀀠be caused Ex settlement
of the foundation soil or 􀁾be built during Eonstruction. Depressions cause roughness and, when filled with water of sufficient depth, could cause hydroPLaning of aircraft. severity
Levels. a. Low severity level (L). Depression can be observed or located Ex staIned areas, only sITghtyY affects pavement riding quality, and may cause hydroplaning potential on runways
(see measurement criteria below). b. Medium severity level (M). The depression can be observed, moderately affeCts pavement riding quality, and causes hydroplaniex potential on runways
(see measurement criteria below). 􀁾􀀠High severity level (H). The depression can be readily observed, severely affects pavement riding quality, and causes definite hydroplaning potential
(see measurement criteria below). Measuring Procedure. Depressions are measured in square feet of surface area. The maximum depth of the depression determines the level of severitY.
This depth can be measured Ex placing 􀁾􀀠10-ft straightedge across the depressed area and measuring the maximum depth in inches. Depressions larger than 10 ft across must be measured
􀁾either visual estimation or Ex direct measurement when filled with water. 5-35 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀠 Maximum
Depth of Depression Runways and Taxiways and Severity High-Speed Taxiways Aprons 1/2 _ 1 in.L M 1 2 in.1 in.--H > 1 in. > 2 in. Additional Criteria 1. Depressions are often detectable
by visual examination of the pavement surface. especially by sighting along the surface from a prone position. Depressions can also be identified with a ten foot straightedge. 2. Standing
water and stains do not outline the boundaries of a depression. When present, they merely confirm its presence. Do not rely on these indicators as evidence of depressions. The straightedge
is a much more reliable tool. 3. Visual examination for presence of depressions on aprons and taxiways is usually sufficient. Visual examination is not adequate for detection of the
presence of depressions on a runway. Use a straightedge and examine at least 20 percent of the Sample Unit surface to confirm the presence or absence of depressions. If depressions are
present, investigate the entire surface. 4. The only severity criterion for this distress type is maximum depth. Depth is measured under a ten foot straightedge. Severity of a depression
is a function of the maximum such measurement in the area of distress. 5. Always measure for depth of depression under the straightedge. Do not estimate. Shadows can be very deceiving.
6. Be alert to distinguish swells from depressions. Envision the surface as it was originally constructed. Depressions and swells may exist in the same area. When in doubt, record depressions.
7. The size of a depression may be measured with a ten foot straightedge if points of contact (representing the distress boundary) are inboard from the 5-36 
􀁾􀁎􀁎􀁎__􀁾􀁟􀁎􀁎􀁎____ NNNN __􀁾􀁟􀁎􀁎􀁟􀁎____N_N__􀁾􀁾_____N _______________ 􀁾________ _Airport Pavement Inspection by PCI ends of the straightedge. Larger areas may be defined by
sliding a straightedge out from center until the leading end breaks contact with the surface as in Figure 5-57. Then measure inboard from point of contact until m1n1mum measurable clearance
is located as in Figure 5-58. Mark this pOint with paint or crayon as the depression boundary. LOCATING BOUNDARY OF LARGE DEPRESSIONS Figure 5-57 Figure 5-58 LOCATING AND MEASURING DEPRESSIONS
ON RUNWAYS Figure 5-59 Figure 5-60 5-37 
􀁾􀁎__N ___􀁾___ N ________________________ 􀁎􀁾_____􀁾_____________ 􀁾__ 􀁾______ _Airport Pavement Inspection by PCI DEPRESSIONS (?) AFTER RAIN Figure 5-61 The only thing water on
pavement indicates is a "bird bath". Presence of a depression can only be determined by measuring under a 10 foot straightedge. Size of a depression, if present, can only be determined
by meaurement. MEASURING FOR DEPRESSION AT FACILITY BOUNDARY Incorrect Correct Figure 5-62 Figure 5-63 These figures show a "bird bath" at intersection of a runway with a taxiway. Grade
change at the intersection is by design. Therefore, placement of the straightedge should not be across the grade Change. 5-38 I 
􀁟􀁎􀁾􀁾___􀁾______ 􀁎􀁾􀁟􀁎____________________________________ ______________ _Airport Pavement Inspection by PCI DEPRESSION AT TRANSVERSE CRACK Figure 5-64 Subsidence at this L &
T crack is further than 6 inches from the crack. Pavement pieces are larger than two feet. This condition is recorded as a Depression plus one medium severity L & T, and two low severity
L & T cracks. DEPRESSION CAUSED BY POOR CONSTRUCTION Figure 5-65 The elevation differential shown at Figure 5-65 is caused by a poorly matched paving lane joint. However, the condition
can cause water to pond, leaving a hydroplaning potential on the pavement. Placement of the straightedgeis important in obtaining accurate measurement. Place the end of the straightedge at the high side of the construction jOint. Measure for depression on the low side under the full 10
foot straightedge. 5-39 
􀁾􀁟􀁾􀁾􀁟􀁾􀁟􀁎􀁟􀁾􀁾_______ N_____________ 􀁾􀁟􀁾________ ______ 􀁾____ ______________ _Airport Pavement Inspection by PCI JET BLAST EROSION -DISTRESS NO.6. Standard Text. Description.
Jet blast erosion causes darkened areas on the pavement surface where bituminous binder haS-been burned or carbonized. Localized burned areas may vary 􀁩􀁮􀁾􀁥􀁰􀁴􀁨􀀠up !£ approximately
1/2 inch. severity Levels. No degrees of severity are defined. It is sufficient to indicate 􀁴􀁨􀁡􀁾􀁪􀁥􀁴􀀠plast erosion exists. Measuring Criteria. Jet blast erosion is measured in
square feet of S"ii"rface area. Additional Criteria 1. Jet blast erosion damage is caused almost exclusively by ram jet engines of military fighter aircraft. Turbofan engines of the
civilian fleet and military cargo aircraft disperse jet blast so that pavement damage rarely results. 2. Look for this distress type at airports with a history of significant military
operations. Jet blast erosion is most commonly found at the ends of runways where aircraft "spool up" before releasing brakes for takeoff. JET BLAST EROSION Figure 5-66 Figure 5-67 5-40

I N _____􀁎􀁎􀁎􀁎􀁎􀁟􀁾___ 􀁎􀁎􀁎􀁎􀁾____ N __NN ______􀁎􀁎􀁟􀁾􀁾_______􀁾____N_N __N ___ N ____ 􀁾􀁎Airport Pavement Inspection by PCI \ \ JOINT REFLECTION CRACKING FROM PCC (LONGITUDINAL
AND TRANSVERSE) DISTRESS NO.7. Standard Text. Description. This distress occurs only on pavements having 􀁾􀀠asphalt or tar surface over a portland cement concrete-rPCey-slab. This category
does not include reflection cracking from any other 􀁾of base (i.e., cement stabilized, lime stabilized)7 Such cracks are listed 􀁾􀀠-rongitudinal and transverse cracks. Joint reflection
cracking is caused mainly 􀁾movement of the PCC slab beneath the asphaltic concrete (AC) surface because of thermal and moisture changes. It is not loadrelated. However, traffic loading
may cause 􀁾􀀠breakdown of the AC near the crack, resulting in spalling. If the pavement is fragmented along 􀁾􀀠crack, the crack is said to be spalled. A knowledge of slab dimenSIOns--beneath
the AC-surface will help to identify these cracks. Severity levels. (Severity Severity levels are described above in General Comments, item 9, page 5-5). Measuring Procedure. Joint reflection
cracking is measured in linear feet. The length and severity level of each crack should be identified and recorded. If the crack 􀁾not have the same severity lever-along its 􀁥􀁮􀁴􀁾􀁲􀁥􀀠length,
each portion should be recorded separately. For example, 􀁾􀀠crack that is 50 ft long may have 10 ft of 􀁾􀀠high severit;;;-crack;" 20 ft of 􀁾􀀠medium severity, and 20 ft of a lIght
severity. These would all be recorded separately. Additional Criteria 1. Joint reflection cracking is pattern craCking. Look for the underlying PCC pavement jOint pattern to be evidenced
on the surface. The pattern may be difficult to distinguish in early stages of reflection. It will be most noticeable when looking out over a large expanse of pavement. Cracks may be
intermittent in early stages, but the pattern will cover the entire surface. Joint reflection cracks follow very straight lines. 5-41 
􀁾􀀠􀁾􀀠􀁾 __ N ____ N ____________ N ___ ______________ ____________ _ _______________Airport Pavement Inspection by PCI JOINT REFLECTION CRACKS Figure 5-66 Figure 5-67 2. Joint reflection
cracks may "meander" back and forth across the PCC joint, but the cause of the crack, and its relationship to the underlying joint will be obvious. JOINT REFLECTION CRACK W/L & T CRACK
Figure 5-68 One of the cracks shown in Figure 5-68 is a Joint Reflection crack. The other may be from shrinkage in the surface or a reflection of a crack in the underlying PCC pavement.
only one can be recorded as Joint Reflection Crack. The other must be a L & T crack. (A secondary crack within 6 inChes of the primary is used to rate severity of the primary crack).
5-42 
____􀁎􀁎􀁟􀁎􀁾___􀁾􀁾____________ 􀁾___N _________􀁾_______________________􀁾___ _Airport Pavement Inspection by PCI LONGITUDINAL AND TRANSVERSE CRACKING (NON-PCC JOINT REFLECTIVE) -DISTRESS
NO.8. Standard Text. Description. Longitudinal cracks 􀁾parallel to the pavement's center line or laydown direction. they may be caused 􀁾􀀨􀁡􀁲􀀭a poorly constructed paving lane joint,
(b) shrinkage of the AC surface due to low temperatures or hardening of the asphalt, or-rc) 􀁾􀀠reflective crack caused 􀁾􀀠cracks beneath the surface course, including cracks in pce
slabs (but not at pee joints). Transverse cracks extend across the pavement at approximately right angles to the pavement's center line or direction of laydown. They may be caused by
items!? £E. £ above. These types of cracks are not usually loadassociated. If the pavement is fragmented along cracks, the crack is said to be spalled. Severity Levels. (Severity levels
are described above in General Comments, item 9, page 5-5). Measuring Procedure. Longitudinal Longitudinal and transverse cracks are measured in linear feet. The length and severity
of each crack should be identified and recorded. 􀁉􀁾􀀠the crack does not have the 􀁾􀀠severity level-aIong its entire length, each portion of the crack having 􀁾􀀠different severity
level should be recorded separately. For an example 􀁾joint reflection cracking. Additional Criteria 1. Diagonal cracks are recorded as longitudinal/transverse unless clearly associated
with alligator or slippage cracking. 5-43 
􀁎􀁟􀁎􀁾􀁎􀁾__N ______􀁾􀁟􀁾_______________________________ 􀁾___________________Airport Pavement Inspection by PCI OIL SPILLAGE -DISTRESS NO.9. Standard Text. Description. oil spillage
is the deterioration 􀁾􀀠softening of the pavement surface caused by the spilling of oil, fUel, 􀁾other solvents. Severity Levels. No degrees of severity are defined. It is sufficient
to indicate that oil spillage exists-.Measuring Procedure. oil spillage is measured in square feet of surface area. Additional Criteria 1. A stain is not a distress unless material has
been lost or binder has been softened. Use a knife blade to check for stability of binder in the stained area. If hardness is approximately the same as on surrounding pavement, and if
no material has been lost, do not record as a distress. Checking For Surface Damage Figure 5-69 5-44 
___􀁾􀁾___N ______􀁎􀁟􀁾􀁾_____􀁾______􀁾􀁟􀁎􀁎􀁟􀁎􀁾􀁟􀁾􀁟􀁎􀁎􀁎____ N _______ 􀁾􀁾__________ _Airport Pavement Inspection by PCI 2. DO not record oil spillage when less than 25 square
feet of area in a sample unit is damaged. OIL SPILLAGE Figure 5-70 Figure 5-71 Oil spills are typically found around fuel pumps and in parking areas. 5-45 
1 􀁾􀁟􀁎􀁟􀁎􀁟􀁎􀁾____ N __ N _______ N _________________________________________􀁾__ _Airport Pavement Inspection by PCI PATCHING AND UTILITY CUT PATCH -DISTRESS NO. 10. Standard Text.
Description. A patch is considered a defect, no matter how well it is performing. Severity Levels. a. Low severity level (L). Patch is in good condItIon and is performing-9atisfactorIIy.-b.
Medium severity level (M). Patch is somewhat deteriorated and affects -riding quality to some extent. c. High severity level (H) • Patch is badly deteriorated and affects ride quality
signHicantly. Patch soon needs replacement. Measuring Procedure. Patching is measured in square feet of surface area. However, if a single patch has areas of differing severity levels,
these areas should be measured and recorded separately. For example, 􀁾􀀠25 sq-ft patch may have 10 sq ft of medium severity and 12 sq ft of light severity. These areas should be recorded
separately. Additional Criteria 1. It is sometimes difficult to distinguish a patch from a leveling course, or "skin patch". To be recorded as a distress, a patch must replace original
pavement. Therefore, do not record maintenance overlay, placed to level a surface, as a patch. Pavement Skin Patch No Distress Figure 5-72 j 5-46 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀁾􀀭􀁾􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀠 2. A clean
sawed edge is the best indicator of a patch. This clearly represents a replacement of material. A feathered edge requires additional investigation. Usually, a feathered edge indicates
additional material on an original surface. Do not record feathered edge pavement as a patch unless it is possible to determine that original pavement has been removed and replaced.
A reflective crack paralleling the feathered edge is an indicator of pavement replacement. 3. The edges of a patch are rated as longitudinall transverse cracks. Crack density is linear
feet of crack divided by area of patch. (Note: On small patches it is possible for calculated density to exceed 100%. In such cases, use the 50+ column from Table 5-2.) PATCH Figure
5-73 Edges of the patch are considered L & T cracks and are used to rate patch severity. 4. A very large patch, or feathered edge pavement, may qualify as a separate Feature. If the
total area is more than 2500 square feet, establish a separate Feature. 5. Patch severity is determined by summing deduct points of distress types from Table 5-2. 5-47 
􀁟􀁎􀁟􀁾_________________________________ N ___________________________􀁾__ _ Airport Pavement Inspection by pcr 􀁾􀀻􀀢􀁾....TABLE 5-2 Density (% ) Distress Severity <20 20 -50 50+ Alligator
(1) L 4 5 7 M 6 7 8 H 7 11 15 Bleeding (2 ) -4 6 7 Corrugation (4) L 3 5 7 M 5 7 9 H 6 8 11 Depression (5) L 3 4 6 M 4 5 8 H 5 7 10 Long/Trans (8) L 2 4 5 M 3 5 7 H 5 8 10 Ravel/Weather(12)
L 1 2 3 M 2 3 5 H 5 7 8 Rutting (13 ) L 3 4 5 M 4 6 8 H 6 9 11 Slippage (15) -5 7 8 Swell (16 ) L 2 3 4 M 3 5 7 H 6 7 11 Rate patch as fOllows: Low severity -< 8 points Medium severity
-8 to 15 points. High severity -> 15 points. 5-48 
I I 􀁾􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾 _____ __ __________________ N ________ ____ ____ _____ ___ ___________Airport Pavement Inspection by PCI POLISHED AGGREGATE -DISTRESS NO. 11. Standard
Text. Description. Aggregate polishing is caused by repeated traffic applications. Polished aggregate is present when close examination of 􀁾􀀠pavement reveals that the portion of aggregate
extending above the asphalt is either very small, or there 􀁾􀁾􀀠rough 􀁾􀀠angular aggregate particles to provide good skid resistance. Severity Levels. No degrees of severity are defined.
However, the degree of polishing should be significant before it is included in the condition survey and rated as a defect. Measuring Procedure. Polished aggregate is measured in square
feet of surface area. Additional Criteria 1. Polished aggregate is very rare on airport pavement. The necessary criterion is that aggregate be smooth and polished. Even uncrushed stones
usually have creases and pits in the surface which are visible to close examination. These imperfections give friction properties necessary to safe aircraft movements. If such irregularities
exist on aggregate visible at pavement surface, the aggregate is not polished. 2. Traffic is not essential to the presence of polished aggregate. River stone may have been polished by
nature before being incorporated into the pavement. 3. Snow plows may shear stones at a pavement surface. These exposed aggregate are not polished. 4. When in doubt, do not record this
distress. Polished aggregate should exist over at least 25 percent of the sample unit surface before being recorded. 5-49 
􀁾􀁟􀁎____􀁾􀁟􀁾______N ______􀁎􀁾___N_N ____ 􀁾________􀁾_________ _ 􀁾____________ _Airport Pavement Inspection by PCI RAVELING AND WEATHERING -DISTRESS NO. 12. Standard Text. Description.
Raveling and weathering 􀁾the wearing away of the pavement surface caused £l the dislodging of 􀁡􀁾􀁧􀁲􀁥􀁧􀁡􀁴􀁥􀀠particles and loss of asphalt or tar b1nder. They may indicate that
the asphalt 􀁾􀁩􀁮􀁤􀁥􀁲􀀠has hardened sIgnificantly.---Severity Levels. a. Low severity level (L) • Aggregate or binder has started to wear away with few, if any, loose particles. ---------b.
Medium severity level (M). Aggregate and/or binder has 􀁾􀀠away with some loose and missing particles:The surface texture is moderately rough and pitted. c. High severity level 􀁾􀀠Aggregate
and/or binder has 􀁾away with 􀁾􀀠large amount of loose and misSing particles. The surface texture is severely rough and pitted. Measuring Procedure. Raveling and weathering are measured
in square feet of surface area. Additional Criteria 1. This is a materials related distress type often uniformly evident over large areas of pavement surface. If caused by construction,
it may be found in lanes as from a bad trUCkload of mix, or in strips paralleling paving lanes as from a cold spot on a screed or poor compaction on one side of a longitudinal construction
joint. 2. The deduct curves for this distress type dictate that a significant amount of material loss be evident. Discoloration or bleached appearance of the pavement surface, or large
amount of exposed stone does not justify recording as a distress. 3. Low severity is recorded when coarse aggregate at the surface of the pavement is exposed to a depth of half the diameter
of individual stones. The surface may be pitted from aggregate loss, but 5-50 
___􀁾____ NN _______________N ____ 􀁾􀁾____________􀁾_______________________􀁾􀀠Airport Pavement Inspection by PCI pits should not be larger than a wallet, and pitted surface should
not comprise more than 10 percent of the area being measured at low severity. Areas of low severity distress smaller than 25 square feet are not recorded. 4. Medium severity is recorded
in areas where more than 10 percent, but less than 50 percent of the top layer of coarse aggregate in the measured area has raveled away. Areas of medium severity distress smaller than
25 square feet, when in larger areas of low severity distress, are included at low severity. 5. High severity is recorded in areas where more than 50 percent of the top layer of coarse
aggregate in the measured area has raveled away. Any area larger than 5 square feet in which all of the top layer of coarse aggregate has raveled away is measured separately and recorded
at high severity. 6. Pavement with chip seal surface treatment may appear to be raveled and weathered. Do not record this distress type on pavement which has received a surface treatment.
NO DISTRESS -RAVELING AND WEATHERING Figure 5-74 Figure 5-75 In Figure 5-74 surface aggregate is obviously exposed, and, in Figure 5-75 there is some pitting at the surface, but neither
condition is serious enough to be recorded as pavement distress. l 
Airport Pavement Inspection by PCI 􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭-,LOW SEVERITY
RAVELING AND WEATHERING Figure 5-76 In Figure 5-76, weathering has progressed to the point where binder and fines have eroded away from the course aggregate. MEDIUM SEVERITY RAVELING
AND WEATHERING Figure 5-77 Figure 5-77 shows a raveled surface approaching high severity. Nearly 50 percent of surface aggregate has been eroded away. 5-52 
__􀁾􀁾􀁾__􀁾__􀁾􀁎___􀁾􀁎􀁎􀁎􀁎____ 􀁾􀁾􀁟􀁎__NNNN ___N __N ____________N _______________Airport Pavement Inspection by PCI HIGH SEVERITY RAVELING AND WEATHERING Figure 5-78 Figure 5-78
shows a condition where nearly all the surface aggregate has been eroded away. NO DISTRESS Figure 5-79 FUTURE DISTRESS Figure 5-80 Figure 5-79 shows an pavement is designed open graded
as a surface friction course course. with a The high percentage of voids between aggregate particles. Figure 5-80 shows a contractor induced distress. 5-53 
---------. ! Airport Pavement Inspection by pcr RUTTING -DISTRESS NO. 13. Standard Text. Description. A rut is a surface depression in the wheel path. 􀁐􀁡􀁶􀁥􀁭􀁥􀁮􀁾􀁵􀁰􀁔􀁩􀁦􀁴􀀠may
occur along the sides of the 􀁲􀁵􀁴􀁾􀀠however, in many instances ruts 􀁾noticeable only after a rainfall, when the wheel paths are filled with -water. Ruttrng-stems from 􀁾􀀠permanent
deformation in any of the pavement layers 􀁾􀀠subgrade. usually caused 􀁾􀀠consolidation 􀁾􀀠lateral movement of the materials due to traffic loads. significant rutting 􀁾􀀠􀁬􀁥􀁡􀁤􀁾􀁯􀀠major
􀁾􀁴􀁲􀁵􀁣􀁴􀁵􀁲􀁡􀁬􀀠failure of the pavement. Severity Levels. Mean Rut Depth Criteria Severity All Pavement Sections L 1/4 =.ill in. M > 1/2 =lin. H > 1 in. Measuring Procedure. Rutting
is measured in square feet of surface area, and its severity is determined 􀁾􀀠the 􀁾depth of the rut. To determine the mean depth, a straightedge--sFiOuld be laid acroSsthe rut and
the depth measured. The mean depth in inches should be computed from measurements taken along the length of the rut. Additional Criteria 1. Rutting in a single wheel path is usually
quite evident. However. rutting can occur over larger expanses of pavement on aprons and taxiways where traffic is not channelized. 2. Locate rutting by visual examination and with a
straight edge. as with depressions. 3. Boundaries of the distressed area is measured in the same manner as are depressions. Measuring rut depth, however, is somewhat different. Minimum
distress depth of a rut is 1/4 inch. irrespective 5-54 
Airport Pavement Inspection by PCl of whether it occurs on a runway, taxiway or apron. Rating is based on mean depth, not maximum depth as with depressions. 4. Wheel tracks left in pavement
by rollers or other equipment while the mix was still hot during construction are not recorded as ruts. They are depressions. 5. Uplift associated with rutting is recorded as part of
the rut distress: not as swell. 6. Rutting can often occur in areas not normally associated with aircraft traffic lanes, as near edges of taxiways and runways. These may have been caused
by maintenance vehicles or snow plows. Rutting may also occur near fuel tanks, caused by bulk fuel tankers: or near fuel truck parking areas, or along the front of rows of tiedowns on
an apron. Record all rutting caused by ground support vehicle traffic. NO DISTRESS Figure 5-81 Depth of rut is less than 1/4 inch. 5-55 
􀁾􀁾􀁟􀁾􀁎􀁾􀁟􀁾_____ 􀁾__N ____________________ 􀁾_______________ N ______________Airport Pavement Inspection by PCI MEDIUM SEVERITY RUTTING Figure 5-82 Rutting shown at Figure 5-82
is caused by a L & T crack and is associated with alligator cracking. Mean depth exceeds 1/2 inch. HIGH SEVERITY RUTTING Figure 5-83 Ruts shown in Figure 5-83 are caused by parked aircraft
on unstable pavement. Mean depth exceeds one inch. One typical "wheel basin" is measured and the area multiplied by the number of "basins". 5-56 
􀁾􀁎􀁎___NNNN ___NNNN ____N ____NN ________________________________________Airport pavement Inspection by PCI SHOVING OF ASPHALT PAVEMENT BY PCC SLABS -DISTRESS NO. 14. Standard Text.
Description. PCC pavements occasionally increase in length at ends where they adjoin flexible pavementS (common1¥, referred to !! "pavement growth"). This "growth' shoves the asphalt-or
tar-surfaced pavements, causing them to swelr-and crack. The PCC slab "growth" is caused £x. 􀁾􀀠gradual opening.!!l2. of the joints !! they are filled with incompressible materials
that prevent them from reclosing. Severity Level. a. Low severity level (Ll. A slight amount of snovrng has occurred with -rrttle-effect on ride quality and 􀁾breakup of the asphalt
pavement. b. Medium severity level (M). A significant amount of shoving has occurred, causing moderate roughness and little or no breakup of the asphalt pavement. c. High severity level
(H). A large amount of snovrng-has occurred, caUSIng severe roughness or breakup of the asphalt pavement. Measuring Procedure. Shoving is measured £x. determining the area in square
feet of the swell caused £x. shoving. Additional Criteria 1. This distress type only occurs at interface between flexible and rigid pavement. It is only recorded on the flexible pavement
side of the interface. 2. Evidence of compression of the flexible pavement by rigid pavement is necessary. A ridge left by poor construction of an adjoining flexible pavement is not
a shoving distress. 3. Rate shoving as follows: a. Measure vertical displacement as with swell. 5-57 
􀁾􀁟􀁎􀁟􀁎􀁟􀁎􀁾􀁎􀁟􀁎_________N ____________N _____N __􀁾_________________________Airport Pavement Inspection by PCI b. Examine pavement surface condition for evidence of other distress,
such as cracking. c. Rate severity of swell and other distress conditions separately. d. Record severity of the shoving distress at the highest of the distress severities meas! ured.
I 4. Since areas of potential shoving are so limited in a pavement Facility, the presence of this distress might escape a sampling survey. Any time shoving is identified on a project,
document the distress by designating sample units containing shoving as "additional" sample units. If the distress is not contained in any designated sample unit, inspect additional
sample units to incorporate the distress into the survey. 5-58 
__ 􀁾􀁾􀁎􀁎___􀁾􀁟􀁎􀁎_______N _________N ____________________________________􀁾􀀠Airport Pavement Inspection by PCI SLIPPAGE CRACKING -DISTRESS NO. 15. Standard Text. Description. Slippage
cracks are crescent-or half-moon-shaped cracks having two ends pointed away from the direction of traffic. They are produced when braking £E turning wheels cause the pavement surface
to slide and deform. This usually occurs when there is a low strength surface mix or poor bond between the surface and next layer of pavementstrUcture. ------Severity Levels. 􀁾degrees
of severity are defined. It is sufficient to indicate that 􀁾􀀭􀁳􀁲􀁩􀁰􀁰􀁡􀁧􀁥􀀠crack-exIStS:Measuring Procedure. Slirpage cracking is measured in square feet of sur ace area. Additional
Criteria 1. This is not a common distress type on airports. It might well be associated with corrugations as the two distress types have similar cause factors. 2. Slippage cracks may
be distinguished from surface blemishes, such as roller marks left during construction in that they extend through the surface course of pavement to the underlying slippage layer. 3.
Do not record circular surface blemishes left by turning and braking aircraft on tender pavement. SLIPPAGE CRACKING Figure 5-84 ;9 
_________________________________________________________ _ --------_______NNN Airport Pavement Inspection by pel SWELL -DISTRESS NO. 16. Standard Text. Description. Swell is characterized
by 􀁾􀀠upward bulge in the pavement's surface. A swerl may occur sharply over a small area or as a longer, gradual wave. Either type of -swelr-can-be accompanied £l surface cracking.
􀁾􀀠sweII is usually caused £l frost action in the subgrade £E by swelling soil, but 􀁾􀀠 small swell can also occur on the surface of an asphalt overlay-(over pec) as 􀁾􀀭􀁲􀁥􀁳􀁵􀁬􀁴􀀠of
a bIowu-p in the pce slab. Severity Levels. a. Low severitx level (L). Swell is barely VIsible and has 􀁾􀀠minor effeCt 2£ the pavement's ride quality 􀁾􀀠determined 􀁾the normal aircraft
speed for the pavement section under consideration. 􀁾􀁌􀁏􀁗􀀠severItY swells may 􀁾always be observable, 􀁾their existence 􀁾be confirmed £l driving 􀁾􀀠 vehicle over the section at
the normal aircraft speed. An upward acceleration will occur if the swell is:present. ---b. Medium severit¥ level (M). Swell can be observed without dLfficulty and has 􀁾􀀠signIrIcant
effect 􀁾the pavement's ride quality as determined 􀁾􀀠the normal aircraft speed for the pavement section under consideration. 􀁾􀀠High severity level (Hl. Swell 􀁾􀀠be readily observed
and severely affects the pavement's ride quality at the normal aircraft speed for the pavement section under consideration. Measuring Procedure. The surface 􀁾of the swell is measured
in 􀁾􀁾􀁾􀀠 feet. The severity rating should consider the type of pavement section (i.e., runway, taxiway, or apron). For example, 􀁾􀀠swell of sufficient magni􀁾!2 cause considerable
roughness 2£ 􀁾􀀠runway at hLgh speeds would be rated 􀁾􀁾severe than the same swell located 2£ an apron or taxiway where the normal aircraft operating speeds 􀁾􀀠much lower. The following
guidance is provided for runways: 5-60 
___ N ____________________________________________􀁾____ 􀁎􀁾􀁾____________Airport Pavement Inspection by PCI Severity Height Differential L 􀁾􀀠ill in. =M 3/4 1-1/2 in. H > 1-1/2 in.
Additional Criteria 1. Man made structures, such as catch basins, tiedown anchors or in-pavement light fixtures, which move differentially from the surrounding flexible pavement, can
cause this type of distress. Swell is quite a common result of such structures in an underlying pavement reflecting movement through a flexible overlay. NO DISTRESS Figure 5-85 The distress
in Figure 5-85 is caused by an in-runway light in an underlying pavement layer. It is not recorded because the area is incidental. 2. Rate severity on high speed taxiways using measurement
criteria provided above. Double the height differential criteria for other taxiways and aprons. 3. Measuring swells requires a slightly different technique than measuring ruts and depressions.
Locate the highest point of the swell. Rest a ten foot straightedge on that point so that both ends are equal distance above pavement. Measure this distance to establish severity rating.
5-61 
􀁟􀁾􀁟􀁎􀁟􀁾􀁟􀁎__N _____N ______________ N ____________________________________Airport pavement Inspection by PCI I I ..1 LOW SEVERITY SWELL Figure 5-86 The distress shown at Figure
5-86 is caused by frost heave from a cable trench. It is on a taxiway and is less than 1-1/2 inch high. .I HIGH SEVERITY SWELL Figure 5-87 5-62 
􀁾___NN ___􀁾􀁎___N _______􀁾__________________N _________________________ _Airport Pavement Inspection by PCI \ LOW SEVERITY SWELL Figure 5-88 The distress shown at Figure 5-88 represents
an attempt at crack sealing. The result is a bump in the runway causing reduction in rideability. This distress rates as a medium severity L & T crack (filler is not pliable) and a low
severity swell. This is not a patch (does not replace original material). 5-63 
, . 􀁟􀁾􀁟􀁾__ 􀁾__􀁾__ 􀁾_______ N_N ________ 􀁾___________________________ N ________ 􀁾􀀠Airport Pavement Inspection by PCI Rigid pavement General Comments 1. Durability "0" cracking,
in advanced stages, results in loss of material at a joint or corner which resembles loss due to spalling. If the tell tale pattern of fine line discolored cracks is evident around the
area of lost material, record the distress as "0" cracking. If "0" crack evidence is absent, record spalling. It may be appropriate to record that both distresses exist in a slab. 2.
"0" cracking along a longitudinal, transverse and diagonal (L/T/O) crack contributes to the severity rating of the L/T/O crack, and is not recorded as "0" cracking unless the "0" crack
pattern extends to at least 3 inches from the opposite face of the crack or until cracks on opposing sides of the L/T/O crack are at least 3 inches apart. 3. Any loose or missing pieces
at a slab joint or corner are not considered in identification of distress types unless the resulting void is at least 3 inches wide measured perpendicular from the opposite joint face
to the point where the void is 1/4 inch deep. Such voids are repairable by jOint sealer. This interpretation is based on an FAA standard of 3 inch maximum allowable width for open trench
in an air traffic area. 4. Spalls are created by the same types of force which create blowups. Spalling results from localized compressive forces usually caused by incompressibles in
a joint. The result is failure evidenced by a diagonal shear plane from the joint face to the surface. Blowups, on the other hand, result from compressive failure of either or both adjoining
slabs through the full depth of pavement. A spall may present a buckled appearance immediately following failure. However, individual loose pieces will soon be dislodged by traffic,
or may be lifted out by hand, to reveal the classic diagonal break characteristic of spalling. If the slab face appears to be otherwise undamaged, the distress is recorded as a spall.
5. Joints and cracks often collect debris which can obscure joint filler. This debris must be removed before filler can be evaluated. 00 not read sand 5-64 
􀁟􀁾􀁎􀁟􀁾􀁎_______􀁾_____ 􀁾􀁾________________________________􀁾􀁾______________Airport Pavement Inspection by PCI I \ I or grass clippings as evidence of unsatisfactory jOint/crack
filler. 6. Try to determine degree of chipping under filler which has overflowed the surface. Chipping affects severity independently of filler. 7. A crack wider than three inches rates
at high severity regardless of filler condition.However, be sure to measure crack width between vertical walls, not from edges of chips or spalls. S. l/S inch is the smallest measurable dimension in rating severity of Blowup and Settlement/Faultin
g. 9. Distress conditions in structural pavement (i.e. pavement designed to isolate a structure from the catch basin) are not recorded. 10. A PCI survey provides a record of the condition
of pavement at an instant in time. Record what you see, not what you believe, or think will be. 11. Pavement in excellent condition can be fairly represented with a reduced sampling
rate. When authorized by the OWner, OWner, pavement with PCI above 90 may be inspected at a 10 percent sampling rate. This requires that all inspected sample units have PCI above 90.
Inspectors must visually confirm that inspected sample units are, in fact, representative of the pavement. Cracking Distress Several distress types are rated for severity on the basis
of associated crack patterns and severity. Since determination of crack severity is the same for all distress types, cracking distress is described below. Standard Text. Crack Severity
Levels. a. Low severity level (L). Crack has little or no spalTIng with no loose particles. If nonfilled, it has 􀁾􀀠mean width less than approximately l/S in. 􀁾􀀠filled crack 􀁾􀀠be
of any width but the filler material must be in satisfactory condition. b. Medium severit¥ joint (M). One of the follow-Lng following cond1tions exists: 5-65 
____ 􀁾__ 􀁾____N ____N _________􀁎􀁟􀁾__N __________________􀁎􀁟􀁾_____ 􀁾_________Airport Pavement Inspection by PCI (1) Filled £E nonfilled crack is moderately spalled with 􀁾loose
particles. (2) A nonfilled crack has a mean width betweenill and 1. in. ----ill 􀁾􀀠filled crack is not spalled or only lightly spalled, but the filler is in unsatisfactory condition.
c. High severity level (H). One of the following condItIOns exists: (1) Filled or nonfilled crack is severely $palled with IDose and missing partICles. (2) A nonfilled crack has a mean
width greater than approximately 1 in.,-creating a tire damage potential. Additional Criteria 1. By our interpretation of inspection criteria, a spall must be at least 3 inches wide
from opposite crack or joint face. As used in the standard discription of crack severity developed by the Corps of Engineers, the word "spall" is also used to define smaller pieces of
loose or missing material. To distinguish between the term, as used in defining crack severity, and the the term, as used in describing spalled concrete, we have introduced the term
"chip". A chip is a small piece of loose or missing concrete at a crack or joint which is less than 3 inches wide, measured perpendicular from the opposite face of the crack or Chip
joint. Figure 5-89 -! A lightly frayed crack edge, as by sandpapering, is not a spall/chip. Spalling/chipping is evidenced by secondary cracks along the primary crack. Little or no spalling
or lightly spalled means chipping defined by secondary cracks which are less than six inches long and occur over less than ten percent of the length of crack. No loose particles means
5-66 .1 
N ___________ 􀁾____ N ________ N __􀁾_________________ 􀁾____________________ 􀁾􀀠Airport Pavement Inspection by PCI loose or missing pieces are smaller than one square inch. 3. Moderate
spalling/chipping means secondary cracks can be of any length but both ends must intersect the primary crack. Individual pieces wider than 3 inches are not cracked and broken. Some loose
particles means loose pieces can be of any length but must be less than three inches wide (chips). Missing pieces wider than 3 inches must effect less than ten percent of the crack length.
4. Do not measure across chips in determining mean crack width. 5. Filler in satisfactory condition prevents entry of water into the crack, is less than 1/2 inch below the surface and
has some elasticity. If cracks have vegetation growing in them, filler is not satisfactory. Absence of satisfactory conditions over less than ten percent of the crack does not make the
condition unsatisfactory. 6. Filled cracks with unsatisfactory filler are subject to width criteria. Pavement condition is not reduced by Owner maintenance. LOW SEVERITY CRACK Figure
5-90 The crack at Figure 5-90 is less than 1/8 inch wide and is not chipped or spalled. If the crack does not intersect a joint at both ends, it is recorded as a shrinkage crack. 5-67

__N __________________________________􀁾􀁟􀁾________􀁾______ 􀁾_____________Airport Pavement Inspection by PCI LOW SEVERITY CRACKS Figure 5-91 Figure 5-92 Crack at Figure 5-91 is approaching
medium severity, but chipping is over less than 10 percent of length and missing pieces are less than one square inch. Crack at Figure 5-92 is at low severity if sealer is in satisfactory
condition. Chips meet low severity criteria. If sealer is in unsatisfactory condition, crack is at low severity if width can be established to be less than 1/8 inch. Note that this crack
has been routed for sealing. Width at surface is not representative of crack width. 5-68 
I N ___N _____________ N ___􀁎􀁾__ 􀁾______ N ____ 􀁾_____________________________􀁾􀀠Airport Pavement Inspection by PCI \ \ MEDIUM SEVERITY CRACKS Figure 5-93 Figure 5-94 Crack at Figure
5-93 is wider than 1/8 inch. Crack at Figure 5-94 has unsatisfactory sealer and meets other medium severity criteria. HIGH SEVERITY CRACK Figure 5-95 Crack at Figure 5-95 is unfilled
and more than one inch wide. 5-69 
_______ N __________________________________􀁾_______________ 􀁾􀁟􀁾_______ _ Airport Pavement Inspection by PCI MEDIUM SEVERITY CRACK HIGH SEVERITY CRACK Figure 5-96 Figure 5-97 Crack
at Figure 5-96 is chipped over more than 10 percent of its length. Crack at Figure 5-97 is severely spalled. 5-70 
􀁾__NN ___􀁾􀀠i .\ \ 1 \ . ! __ N ____________________________􀁾____􀁾___N ___________________Airport Pavement Inspection by PCI BLOWUP -DISTRESS NO. I Standard Text. Description. Blowups
occur in hot weather, usually at a transverse crack 􀁾􀀠joint that is not wide--enough!2 permit expansion of the concrete slabs. The insufficient width is--Usually caused 􀁾􀀠infiltra=
tion of incompressible materials into the joint space. When expansion cannot reTieve--enough pressure, 􀁾􀀠localized upward movement of the slab edges {buckling} 􀁾􀀠shattering will
occur in the vicinity of the joint. Blowups 􀁾also occur at utility cuts and drainage inlets. This type of distress is almost always repaired immediately because of severe damage potential
to aircraft. the main reason blowups are included here is for reference when closed sections 􀁾being evaluated for reopenIng:" Severity Levels. a. Low severity level (L). Buckling or
shattering has not rendered the pavement inoperatIVe, and only 􀁾􀀠slight amount of roughness exists. b. Medium severity level (M). Buckling or shattering has not rendered the pavement
inoperative, but 􀁾􀀠significant amount of roughness exists. c. High severity level (H). 􀁂􀁵􀁣􀁫􀁬􀁩􀁮􀁾􀀠or Shattering has rendered the pavement inoperat1ve. For the pavement to be
considered operational, all roreIgn material -Caused by the blowup must have been removed. Counting Procedure. A blowup usually occurs at 􀁾􀀠transverse crack or joint. At 􀁾􀀠crack,
it is counted 􀁾􀀠being in one slab, but at 􀁾􀀠joint two slabs are affected and the distress should be recorded as occurring in two slabs. Additional Criteria 1. To designate severity,
use twice the elevation differential prescribed for Settlement/Faulting. This measurement may be from upheaval or due to missing materials, or a combination. 5-71 1 
N _____􀁎􀁾_____N ___________________________________􀁾__􀁾􀁟􀁾􀁾___ 􀁾____􀁾____Airport Pavement Inspection by PCI 2. Record blowup on a slab only if the distress is evident on that
slab. Severity may be different on adjacent slabs. 3. Vertical displacement or material loss must be evident over at least ten percent of the joint width to establish the level of severity.
4. If blowup has been repaired by patching, establish severity by differential elevation per foot of patch (ramp). BLOWUP Figure 5-98 Figure 5-99 Low Severity High Severity Blowup at
Figure 5 -98 has been repaired by ramping, and differential elevation on the taxiway is less than one inch per foot of ramp. Blowup at Figure 5-99 is at high severity because differential
elevation at several points is greater than 2 inches. Note that an earlier Blowup at this same joint was patched and ramped to restore serviceability. 5-72 
____________________________Airport PavementN _____ Inspection by PCI NN _______________NNN _______________ CORNER BREAK -DISTRESS NO.2. Standard Text. Description. A corner break is
a crack that intersects the JOints at 􀁾􀀠distance less than 2£ equal to one-half of the slab length on both sides, measured from the corner of the slab. For example, a slab with dimensions
of 25 by 25 ft that has a crack intersecting-the JOInt 􀁾􀀠ft from the corner on one side and 17 ft on the other side is not considered 􀁾􀁲􀁮􀁥􀁲􀀠break.!. it is 􀁾􀀠diagomilcrack:':-However,
􀁾􀀠crack that intersects 7 ft on one side and 10 ft on the 􀁯􀁴􀁾􀁩􀁳􀀠considered a-corner-break.---A--corner break differs from 􀁾􀀠corner spall in that the crack extends vertically
through the entire slab thickness, while a corner spall intersects the jOint 􀁾􀀠an 􀁡􀁮􀁧􀁬􀁥􀁾􀀠Load repetition combined with loss of support and curling stresses usually cause corner
breaks. Severity Levels. 􀁾􀀠􀁾severity level (L). (Use crack severity definitions presented above under Cracking Distress, page 5-64, plus the following). The area between the corner
break and the joints is not cracked. -----b. Medium severity joint (M). (Use crack severity aefinitions presented above under Cracking Distress page 5-64, plus the following). The area
between the corner break and the jOints is 􀁉􀁉􀁧􀁨􀁾􀁣􀁲􀁡􀁣􀁫􀁥􀁤􀀮􀀠􀁾􀀠High severity level (H). (Use crack severity definitions presented above under Cracking Distress page 5-64,
plus the following). The area between the corner break and the joints is severery cracked.--Counting Procedure. A distress slab is recorded as one slab if it (a) contains a -sIngle corner
break, TbT contaIns--more than one -break of a particular severity, or (c) 5-73 
N_N __􀁾__N_N __􀁾__􀁎􀁾____N _____________________________________________􀁾􀀠Airport Pavement Inspection by PCI contains two or more breaks of different severitieS:-For two or more
breaks,--the highest level of severity shOUld be recorded. 􀁾example, a slab containing both light and medium severity corner breaks should be counted as one slab with a medium corner
break. -------------Additional Criteria 1. Lightly cracked means one low severity crack dividing the corner into two pieces. 2. If the corner is faulted 1/8 inch or more, increase severity
to next higher level. If the corner is faulted more than 1/2 inch, rate Corner Break at high severity. (If faulting in corner is incidental to faulting in the slab, rate faulting separately.)
2. The angle of crack into the slab is usually not evident at low severity. Unless crack angle can be determined, to differentiate between corner break and corner spall, use the following
criteria. If the crack intersects both joints more than two feet from the corner, it is a corner break. If either intersect point is closer to the corner than two feet, the crack is
a corner spall or joint spall. LOW SEVERITY CORNER BREAKS Figure 5-100 Figure 5-101 Corner Break at Figure 5-100 is defined by a low sever5-74 
􀁾􀀠􀁾􀀠 􀁾􀀠􀁾􀀠􀁾􀀠􀁾_______N_N ____ ______ ________________ ______ ______ ____ ___________Airport Pavement Inspection by PCI I ity crack with frayed edges. Sealer is unsatisfactory.
Corner Break at Figure 5-101 is defined by a low severity crack with satisfactory sealer. Appearance of the sealer suggests the corner has settled. If measured \ settlement is 1/8 inch
or more, Corner Break is at medium severity. I MEDIUM SEVERITY CORNER BREAK Figure 5-102 Corner Break at Figure 5-102 is defined by a medium severity crack due to spalling wider than
3 inches with missing pieces. HIGH SEVERITY CORNER BREAKS Figure 5-103 Figure 5-104 These corner breaks are severely cracked. Break at Figure 5-104 has also settled. 5-75 
----I #N ___􀁾________________________ 􀁾___􀁾______ N _______ 􀁾___Airport Pavement Inspection by pcr LONGITUDINAL, TRANSVERSE, AND DIAGONAL CRACKS DISTRESS NO.3. Standard Text. Description.
These cracks, which divide the slab into two or three pieces, 􀁾usually caused £l 􀁾􀀠combination of load repetition, curling stresses, 􀁾shrinkase stresses. (For slabs divided into
six or more pieces, see--shattered/intersecting--cracks.r-Low severity cracks 􀁾usually warpins-􀁾􀀠frictionrelated and are not considered major structural distresses. Medium-Qr high
severity cracks 􀁾􀀠usually working cracks and 􀁾considered major structural distresses. -rNote: Hairline cracks that 􀁾only 􀁾􀀠few feet lons and do not extend across the entire slab
are rated as shrinkase cracks.) Severity Levels. Low severity level (L) . (Use crack severity definitions presented above under Cracking Distress page 5-64). Medium severity level (M).
(Use crack severity definitions presented above under Cracking Distress page 5-64, plus the following). The slab is digtlal tehr hsnaa utaoaf £X low severItY cracks. 􀁾􀀠HiSh severity
level (H). (Use crack severity definitions presented above under Cracking Distress page 5-64, plus the following). The slab is divided into three pieces more-crackS, one 􀁯􀁾􀁩􀁣􀁨􀀠is
at least severity. --Countins Procedure. Once the severity has been identified, is recorded as 􀁯􀁮􀁥􀀭􀁳􀁉􀁡􀁾􀀠 Additional Criteria £l two or of medium the distress 1. Longitudinal,
transverse, and diagonal cracking will hereafter be abbreviated as "L/T/D cracking". 2. If the slab is divided into four or more pieces 5-76 
􀁾__􀁎􀁎􀁾_____NN ______􀁎􀁟􀁎􀁟􀁾___N ____________________________N ____________Airport Pavement Inspection by PCI \ by L/T/D cracks, refer to "Shattered Slab/Inter\ secting Cracks"
distress type, below. \ 3. Cracks used to define and rate corner breaks, "0" cracks, patches, shrinkage cracks and spalls are not recorded as L/T/O cracks. 4. Minor spalling (chipping)
means the same as . i little, or lightly. See descriptions under ! Cracking Distress, page 5-64. HIGH SEVERITY L/T/O CRACKING Figure 5-105 Cracks at Figure 5-105 divide the slab into
three pieces, and one crack is at medium severity (wider than 1/8 inch). Note that this is not a corner break since the piece in the corner is defined by two distinct cracks. Note, also,
that both cracks, and the joint at bottom of picture, are pumping. 5-77 
i 􀁾_____ 􀁾______􀁾􀁟􀁾􀁾􀁾___N __________N __ 􀁎􀁾􀁟􀁾____ 􀁾_____________ 􀁾__________􀁾Airport Pavement Inspection by PCI DURABILITY (UD") CRACKING -DISTRESS NO.4. Standard Text.
Description. Durability cracking is caused £l the concrete's inability to withstana-environmental--ractors such 􀁾􀀠freeze-thaw cycles. It usually appears 􀁾􀀠􀁾􀀠pattern of cracks running.
parallel !£ 􀁾􀀠joint or linear crack. 􀁾􀀠dark color1ng 􀁾usually be 􀁾􀀠around the fine durability cracks. This type of cracking may eventually lead!£ disintegration of the concrete
within 1 to 􀁾􀀠ft of the jOint or crack. Severity Levels. 􀁾􀀠Low severity level (L). Pieces 􀁾defined £l light cracks and cannot be removed. b. Medium severity level (M). uD" cracks
are well defined. Small pieces have been displaced. c. High severity level (H). "D" cracking has developed 􀁾􀁾􀀠considerable amount of slab area (greater 􀁾approximately one-quarter
of 􀁾slab (area), and the pieces are well defined and can be removed-eisIIY. -------Counting Procedure. When the distress is located and rated at one severItY, it is counted as one slab.
If more than one severity level is found, the slab is cOiii1ted as having the higher severity distress. For example, if light and medium durability cracking 􀁾located 􀁾􀁾􀀠slab, the
slab is counted as having medium only. Additional Criteria 1. "D" cracking can be outlined by white coloring if leaching is taking place. 2. Except in its very early stages, "D" cracking
is easily distinguishable from corner or joint spalling by the multiplicity and pattern of cracks. When in doubt, rate as a spall. At low severity, the deduct values are nearly identical.
3. The key to a rating of low severity is to recognize the pattern. If pieces are loose or 5-78 
I 􀁾􀁾􀁾􀀠􀁾 __ ______________________N ________________________________________Airport Pavement Inspection by PCI missing, rate the slab at medium severity except disregard loose and
missing pieces within three inches of the corner.\ If the identifiable pattern covers 25 percent or\ more of the slab area and if there are loose or missing pieces, rate the slab at
high severity. If more than five percent of the slab surface is loose or missing, regardless of pattern coverage, rate the slab at high severity. 4. "0" cracking is a function of materials
deterioration and is. therefore. usually evident for considerable distances in paving lanes or along longitudinal joints where water has ponded through the years. LOW SEVERITY "0" CRACKING
Figure 5-106 Figure 5-107 Figure 5-106 shows earliest stages of "0" cracking. "D" cracking at Figure 5-107 is a well defined pattern at low severity since pieces have not begun to separate
from the slab. 5-79 
N _____􀁾___􀁎􀁾􀁟􀁾____􀁾____􀁾􀁾_________􀁾__________________________________Airport Pavement Inspection by PCI LOW SEVERITY "D" CRACKING Figure 5-108 Figure 5-109 "D" cracking in
Figure 5-108 is at low severity with missing pieces within 3 inches of the joint. Figure 5-109 shows "D" cracking on wet pavement. (There is a tendency to rate distresses on wet pavement
at higher severity.) If closer examination discloses loose or missing pieces. this rating will be at medium severity. MEDIUM SEVERITY "D" CRACKING Figure 5-110 Figure 5-111 Figure 5-110
shows "D" cracking at medium severity in the near slab. and at low severity in the other slabs. 5-80 
_______ 􀁾_____ 􀁎􀁾__ 􀁎􀁎􀁎􀁎􀁟􀁾__ N_N ____NNN _____NN_N __________ N ____ 􀁾________ _Airport Pavement Inspection by PCI \ \ \ Each slab must be rated independently. of pattern does
not affect rating until 25 percent of the slab surface, or until the surface is loose or missing. At coverage exceeds 25 percent. Note that size pattern covers 5 percent of Figure 5-111,
'j HIGH SEVERITY "D" CRACKING Figure 5-112 Figure 113 Pattern at Figure 5-112 will cover 25 percent of slab surface if all corners are similar to those shown. Figure 5-113 rates at high
severity "D" cracking due to missing pieces. Rate "D" cracking rather than Patch since liD" cracking is the more severe distress. 5-81 
______ 􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾􀀠􀁾 ___ N ___ ______ ___________________ __________ _ _ ____ _______ _Airport Pavement Inspection by PC! JOINT SEAL DAMAGE -DISTRESS NO.5. Standard Text.
Description. 􀁾􀀠Joint , seal damage is any condition which enables so11 or rocks to accumulate in the jOints or 􀁡􀁬􀁬􀁯􀁷􀀭􀁳􀀭􀀭􀀭􀁳􀁉􀁧􀁮􀁩􀁦􀁩􀁣􀁡􀁮􀁾􀀠infiltration 􀀭􀀭􀁯􀁾􀀠water.
Accumulation of incompressible materialS prevents the slabs from expanding and may result in bUCkling, shattering, or spalIIng. 􀁾􀀠pliable joint filler bonded !£ the edges of the slabs
protects the joints from accumulation of materials and also prevent7 􀁷􀁡􀁾􀁦􀁲􀁯􀁭􀀠seeping down and softening the foundatlon supporting the slab. 􀁾􀀠Typical types of joint seal damage
are: stripping of jOint sealant, extrusion of JOInt sealant, weed growth, hardening of the filler (oxidationy;-loss of bond to the slab edges, and lack 􀁾absenceof sealantin the joIilt':"
Severity Levels. a. Low severity level (L). Joint sealer is in generally good condition-throughout the sectIon7 Sealant is performing well with only 􀁾􀀺􀁭􀁲􀁮􀁯􀁲􀀠amount of 􀁾􀁮􀁹􀀠of
the above types of damage present. b. Medium severity level (M). Joint sealer is in generally fair condition over the entire surveyed section with one or more of the above types of damage
occurring-to 􀁾􀀭􀀭􀁭􀁯􀁤􀁥􀁲􀁡􀁾􀀠degree. Sealant needs replacement within 􀁾􀀠years. c. High severity level (H). Joint sealer is in generally poor condition over the entire surveyed
section 􀁷􀁩􀁾􀁯􀁮􀁥􀀠or more--Qf--rhe above types of damage occurring-to-a severe 􀁤􀁥􀁧􀁲􀁾􀀠Sealant needs immediate replacement. Counting Procedure. Joint seal damage is 􀁾􀀠counted
􀁾􀁾􀀠slab-by-slab basis, but is rated based on the overall condition of the sealant over the entIre-6ection. Additional Criteria 1. Joint sealer is'in satisfactory condition if it prevents
entry of water into the joint, if it is less than 1/2 inch below the joint edge, it has 5-82 
___ ________ __ _________________ _________________ ___________ __ _ 􀁾􀁾􀀠􀁾􀀠􀁾􀀠􀁎􀁾􀀠􀁾􀀠 􀁾􀀠Airport Pavement Inspection by PCI some elasticity, and if there is no vegetation growing
between the sealer and joint face. 2. Joint seal damage is at low severity if ten percent or more of the sealer has debonded from, but is still in contact with, the joint edge. This
condition exists if a knife blade can be inserted between sealer and jOint face without resistance. ·-:·t 3. Joint seal damage is at medium severity if ten percent or more of the joint
has any of the following conditions. (a) Joint sealer is in place, but water access is possible through visible openings no more than 1/8 inch wide. Do not rely on appearance in evaluating
this condition. If a knife blade cannot be inserted easily between sealer and jOint face, this condition does not exist. (b) Joint sealer is more than 1/2 inch below joint edge but less
than one inch. (c) Pumping stains are evident at the joint. (d) Joint sealer is oxidized and and "lifeless" but pliable (like a rope), and generally fills the jOint opening. (e) Vegetation
in the joint is obvious, but does not obscure the jOint opening. 4. Joint seal damage is at high severity if ten percent or more of the joint sealer exceeds limiting criteria listed
above, or if ten percent or more of sealer is missing. 5. Premolded jOint sealer is a compressed rubber or synthetic rectangular strip pressed into the jOint by mechanical means. During
installation a lubricant is applied to facilitate placement. Premolded sealer adheres to the joint walls by friction. It is not "glued" in place. premolded sealer is rated using the
same criteria as above except as follows. (al Premolded sealer must be elastic and must be firmly pressed against the joint walls. (b) premolded sealer must be below the jOint edge.
If it extends above the surface, it can be caught by moving equipment such as snow plows or brooms and be pulled out of the joint. premolded sealer 5-83 
'I 􀁾􀁾􀁾_____ 􀁎􀁟􀁎􀁟􀁾__ 􀁎􀁟􀁎􀁾􀁎􀁟􀁾____ N __ N _____ N ___ 􀁾_____________Airport Pavement Inspection by PCI is recorded at low severity if any part is visible above joint edge.
It is at medium severity if ten percent or more of the length is above joint edge or if any part is more than 1/2 inch above joint edge. It is at high severity if 20 percent or more
is above joint edge or if any part is more than one inch above joint edge, or if ten percent or more is missing. 6. Rate joint sealer by joint segment. Sample unit rating is the same
as the most severe rating held by at least 20 percent of segments rated. 7. Do not rate downstation and right side joints along a sample unit boundary. They belong to adjacent slabs.
Rate only the left and upstation joints along Sample Unit boundaries. 8. In rating oxidation, do not rate on appearance. Rate on resilience. Some joint sealer will have a very dull surface,
and may even show surface cracks in the oxidized layer. This can be misleading. If the sealer is performing satisfactorily and has good characteristics beneath the surface, it is satisfactory.
A pocket knife is essential to joint seal damage evaluation. NO DISTRESS Figure 5-114 Figure 5-115 Joints are not straight and smooth, but sealer is good. 5-84 
__􀁾􀁎􀁎􀁎_____ NNNN __􀁾􀁟􀁾􀁟􀁎􀁎􀁎􀁎􀁎___NNNNN _____NNN ______N __N ______􀁾___N ______Airport Pavement Inspection by PCI \ \ \ i \ I I NO DISTRESS Figure 5-116 Sometimes sand and
debris must be before sealer can be rated (Figure debris. In Figure 5-117, sealer cracked, but clos"er examination reveals excellent material. Figure 5-117 removed from a jOint 5-116).
Do not rate looks weathered and with a knife blade LOW SEVERITY JOINT SEAL DAMAGE Figure 5-118 Figure 5-119 This sequence illustrates joint sealer at low severity. There is no bond between
sealer and joint wall. This condition can only be determined with a knife blade. 5-85 
__N ____􀁾_______􀁾􀁾􀁟􀁎___________________________N ______________________Airport Pavement Inspection by PCI MEDIUM SEVERITY JOINT SEAL DAMAGE Figure 5-120 Figure 5-121 Joint sealer
at Figure 5-120 is visibly separated from the joint wall by less than 1/8 inch. This must be confirmed with a knife blade. Often. sealer will be separated at the top. but bonded to the
joint wall beneath. Vegetation at Figure 5-121 causes severity to be medium. MEDIUM SEVERITY JOINT SEAL DAMAGE Figure 5-122 Figure 5-123 Sealer at Figure 5-122 is bonded to chips. but
chips are 5-86 
I 􀁟􀁾__􀁾􀁎􀁎􀁎􀁟􀁾􀁾__􀁎􀁎􀁎􀁎􀁎􀁟􀁾_________________________􀁾________􀁾_____________ _Airport Pavement Inspection by PCI \ separated. This condition can be corrected by resealing,
\ but present condition is at medium severity. Figure 5-123 shows old sealer which has lost elasticity and bond. Note that grass clippings do not contribute to the rating. MEDIUM SEVERITY
JOINT SEAL DAMAGE Figure 5-124 Figure 5-125 These figures show expansion joints Which have been extruded from the joints by slab expansion. They are tightly sealed as shown, but damage
will be evident when joints open during cold weather. HIGH SEVERITY JOINT SEAL DAMAGE Figure 5-126 Figure 5-127 In Figure 5-126, sealer is badly deteriorated, and in Figure 5-127, sealer
is missing altogether. 􀁾􀀠! 5-87 
___ N __􀁾___ 􀁾􀁟􀁾􀁟􀁎______􀁾___􀁾________􀁾__________􀁾___________________􀁾􀁟􀁾􀁟Airport Pavement Inspection by PCI HIGH SEVERITY JOINT SEAL DAMAGE Figure 5-128 The distress at
this joint is more complex than sealer. Chipping has destroyed bond at the joint wall. Still, the condition can be corrected by sealing the joint. Therefore, if the condition affects
more than 10 percent of the joint segment, it is rated as high severity Joint Seal Damage. 5-88 
___ 􀁾􀁎___􀁎􀁎􀁎􀁎􀁟􀁎􀁎􀁟􀁾__ NN ________􀁾􀁟􀁎􀁎____N ___􀁾_________ NN _ _______________Airport Pavement Inspection by PCI PATCHING, SMALL (LESS THAN 5 SQ FT)-DISTRESS NO. 6 Standard
Text. Description. A patch is an area where the original pavement has been removed and:replaced 􀁾􀀠􀁾􀀠filler material. For condition evaluation, patching is divided into tWO types:
small (less than 5 sq ft) and large TOVer 2 sq ft). Large 􀁰􀁡􀁴􀁣􀁾􀁡􀁲􀁥􀀠described in the next section. Severity Levels. a. Low severity level (L). Patch is functioning well with
little or no deterioration. 􀁾􀀠Medium severity level (M). Patch has deteriorated and/or moderate spalling can be-seen around the edges. Patch material can be disIOdged with considerable
effort. 􀁾􀀠High severity level (M). Patch has deteriorated, either 􀁾􀀠spalIIng around the pat.Ch or cracking within the patch, to a state"" which warrants replacement. Counting Procedure.
If one or more small patches having ,the same severity level are located in 􀁾􀀠slab, it 􀁾􀀠counted as one slab containing that distress. If more than one-severITy level oc'CiiTS, it
is count"Ei"das one slab with the higher severity level being recorded. Additional criteria 1. A patch is actually a separate piece of pavement. Therefore, it is appropriate to rate
patch severity using distress types present in the patch pavement. Use Table 5-3 below, to establish a rating for rigid patches. 2. Edges of a patch are rated as L/T/D cracks, whether
cracks are visible or not. 3. Patches smaller than ten inches on a side or in diameter are not counted (measure diagonal of corner patch). If a patch smaller than ten inches is in failed
condition, record the distress that was corrected by the patch. 5-89 
_________ 􀁾___ 􀁾􀁾__ 􀁾􀁎___ 􀁾____________________ N __________________ 􀁾____ N_Airport Pavement Inspection by PCI 4. Patches less than ten inches wide along joints are not recorded.
TABLE 5-3. Distress 􀁾􀀠Severit:i Points Corner Break (2 ) L 4 M 7 H 9 L/T/O Crack (3) L 2 M 6 H 8 "0" Crack (4) L 2 M 3 H 6 Scaling, etc. (HI) L 2 M 5 H 9 Settlement (ll ) L 4 M 6 H
9 Shattered Slab (12) L 6 M 9 H 12 Spalling, Joint (14 ) L 1 M 4 H 5 Spalling, Corner (15) L 2 M 3 H 5 The following comments pertain to rating of patches. a. Ratepatch at low severity if the sum of distress points from Table 5-3 is less than 4; medium severity if the total points are between 4 and 8, inclusive; and high severity if the total
points are more than 8. b. Rate corner break and spalling only at joints. Otherwise, rate as L/T/D cracking and scaling, respectively. 5-90 
c. Distresses used to rate patches are not used again in rating the slab. d. Rate each occurrence of a distress in a patch separately and add the points. NO PATCH Figure 5-129 Figure
5-130 Patch must replace original material. Figure 5-129 shows a "ramp", or leveling course placed to return a Blowup to serviceable condition. This is not rated as a patch, but should
be investigated and rated as a Blowup. Figure 5-130 shows a joint repair less than 10 inches wide. The distress shown is rated as a Joint Spall if, at its widest point, it is more than
3 inches wide. 5-91 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭PATCHING, LARGE
(OVER 5 SQ FT) AND UTILITY CUT DISTRESS NO.7. Standard Text. Description. patching is the 􀁾􀁾􀀠defined in the previous section. 􀁾􀀠utility 􀁾􀀠is 􀁾􀀠patch that has replaced the original
pavement because of placement of underground utilities. The severity levels of 􀁾􀀠utility 􀁾􀀠patching. are the same as those for regular Severity Levels. 􀁾􀀠Low severity level (Ll.
Patch is 􀁾􀁴􀁩􀁯􀁮􀁩􀁮􀁧􀀠􀁾with very little £E ££ deterioration. 􀁾􀀠Medium severity level eM). Patch is deteriorated and/or moderate spalling can be-Seen around the edges. Patch material
can be dIsIOdged with considerable effort. c. 􀁾􀁩􀀹􀁨􀀠severity level (H). Patch has deteriorate to a state 􀁷􀁨􀁾􀀠causes considerable roughness wIth loose £E easily dislodged material.
the extent of the deterioration warrants replacement of the patCh':Counting Procedure. The criteria are the same as for small patches. Additional Criteria 1. Use criteria prescribed
above, and Table 5-3, as for small patches, but use the following rating procedure. 2. Rate patch at low severity if total points accumulated from Table 5-3 are fewer than 7; medium
severity if total points are between 7 and 15, inclusive, and high severity if total points are more than 15. 5-92 
____􀁾􀁾􀁎􀁟􀁾___________________N ___________ N ___________Airport Pavement Inspection by PCl LARGE PATCH Figure 5-131 NO PATCH Figure 5-132 Patch at Figure 5-131 is larSince the patch
is of asphalt, ger it than must 5 square feet. be rated using rating criteria for a flexible patch (Table 5-2). The patches at Figure 5-132 (both rigid and flexible patches are shown)
are in a slab with high severity scaling. Since the condition of surrounding pavement is more severe than the patches, rate the surface condition and ignore the patches. NO DISTRESS
Figure 5-133 Slab replacement is not a patch. 5-93 
Airport Pavement Inspection by PCI 􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭POPOUTS -DISTRESS
NO.8. Standard Text. Description. 􀁾􀀠popout is 􀁾􀀠small piece of pavement that breaks loose from the surface due to freeze-thaw action in cOmbinatIOn with expanSIVe--aggregates. popoutS
usually range from approximately! to 4 in. in diameter and 􀁾!L1 􀁾􀁾􀀠in. deep. Severity Levels. 􀁾degrees of severity are defined for popouts. However, 􀁰􀁯􀁰􀁯􀁵􀁾􀁳􀀠􀁾􀁾􀀠extensive
before they 􀁾􀀠counted 􀁾􀁾􀀠􀁤􀁾􀁳􀁴􀁲􀁥􀁳􀁳􀁲􀀠􀁾􀀮􀁥􀀮􀀬􀀠average popout 􀁤􀁥􀁮􀁳􀁾􀁴􀁹􀀠􀁾exceed approximately three popouts per square yard 􀁾the entire slab area. Counting Procedure.
The density of the distress must be measured. If there is any doubt about the average being greater than three popouts per square yard, 􀁾􀀠least three random l-sq-yd areas should be
checked. When the average is greater than this 􀁾􀁥􀁮􀁳􀁩􀁴􀁹􀀬􀀠the slab is counted. Additional Criteria 1. Stains from iron-rich aggregate do not identify popouts unless the stones
are missing from the surface. 2. Minimum dimensions of a popout, 1 inch diameter and 1/2 inch deep, eliminate most surface voids left by stone loss. This distress type is not common,
although voids from stone loss are quite common. Be sure a significant number of voids meeting minimum dimension reqUirements are present before recording this distress type. 5-94 
􀁟􀁎􀁾􀁎__ NN ___NN ___NNN ___ N _________ 􀁎􀁾_________ 􀁾_____ N __________________ _Airport Pavement Inspection by pel \ \ I POPOUTS Figure 5-134 Figure 5-135 Figure 5-134 shows a
minimum size void to be called a Popout. Figure 5-135 shows a slab with popouts. 5-95 
􀁟􀁾___N _________􀁾___N_N _______________􀁾􀁟􀁾__________________________ _Airport Pavement Inspection by PCI PUMPING -DISTRESS NO.9. Standard Text. Description. pumping is the ejection
of material Ex water through JOints £E cracks caUSed by deflection of the 􀁾under passing loads. As water is ejected, it car:ies.particles of 􀁧􀁲􀁾􀁶􀁥􀁬􀀬􀀠sand, clay, £E silt 􀁲􀁥􀁳􀁵􀁬􀁴􀁾􀁮􀁧􀀠�
�􀀠􀁾􀀠􀁰􀁲􀁯􀁧􀁲􀁥􀁳􀁳􀁾􀁶􀁥􀀠loss of pavement support. Surface staining and base £E subgrade material 􀁾􀀠the pavement close!£ jOints £E cracks 􀁾evidence of pumping. Pumping 􀁾􀀠jOints
indicates poor jOint sealer and loss of support, which will lead to cracking under repeated loads. Severity Levels. No degrees of severity are defined. It is sufficient to inaIcate that
pumping exists. Counting Procedure. Slabs are counted as follows, one pumping joint between two slabs--is countea-as two slabs. However, if the remaining Joints 􀁡􀁲􀁯􀁵􀁮􀁾􀁴􀁨􀁥􀀠slab
􀁾also pumping, 􀁾slab is added per addItional pumping joint. Additional Criteria 1. Do not be fooled by stains caused by ponding water on the low side of a longitudinal joint. pumping
stains will be intermittent along the joint and will usually fade gradually in direction of flow downslope from the joint. 2. Fines and subgrade materials pumped out of the joint are
excellent evidence of pumping, but be alert to distinguish these from wind blown debris. Furthermore, subgrade materials may be washed or blown away from the joint. Identify pumping
by the tell tale stain. Do not rely on loose material at the joint. 3. A pumping stain may be any color from very dark, caused by subgrade, to brown from base course materials or subgrade,
to near white from bleaching of pavement. Dark stain may also be from joint sealant residue. This may be a result of surface water running in a joint and exiting at point of stain. Such
a stain is not evidence of pumping. 5-96 
􀁾___􀁾___􀁾________ N _____N ___􀁾􀁾􀁟􀁎____􀁾_____________________􀁾􀁾___ 􀁾􀁾__ _Airport Pavement Inspection by pel 4. If in doubt rate as a pumping joint. 5. pumping can occur at
cracks as well as joints. NO DISTRESS Figure 5-136 At first glance, stains at Figure 5-136 seem to be classic pumping stains. On closer examination, however, it is clear that stains
are from ponding water on slabs that have warped, or curled, at joints. Gradient of pavement is down toward top of picture. PUMPING Figure 5-137 Figure 5-138 Both figures show classic
flow patterns diminishing away from the joints. 5-97 
􀁟􀁾__􀁾___􀁾__N _________ N ______􀁾􀁟􀁾________􀁾__􀁾____________ 􀁾􀁟􀁾_______ 􀁾􀁟Airport Pavement Inspection by PCI PUMPING Figure 5-139 Figure 5-140 Stain at Figure 5-139 could
be from ponding water except that gradient is clearly to shoulder. Figure 5-140 shows a classic Pumping stain. PUMPING Figure 5-141 Stain in Figure 5-141 is from joint sealer. Gradient
is critical here. If this is the low point of a vertical curve, stains may be from water running in the joint and being forced out at the bottom of the curve. Otherwise, this is Pumping.
5-98 
\ 􀁾___􀁾􀁾____ NNNN ___N __ NN __________ N_NN _______________􀁾______􀁾____ 􀁾__ _Airport Pavement Inspection by PCI SCALING, MAP CRACKING, AND CRAZING -DISTRESS NO. 10 standard Text.
Description. Map cracking 􀁾􀀠crazing refers to a network of shallow, fine, or hairline cracks that-extend only through the upper surface of 􀁾concrete. The cracks tend to intersect
at angles of 120 degrees. 􀁍􀁾􀁰􀀠cracking or crazing is usually caused 􀁾􀀠over 􀁦􀁾􀁮􀁩􀁳􀁨􀁩􀁮􀁧􀀠the concrete and may lead to 􀁳􀁣􀁡􀁬􀁾􀁮􀁧􀀠of the surface, which is the breakdown
of the slab SUrface to .<:!: depth ofapproximately 1/4 to 1/2 in. Scaling may also be caused 􀁾deicing salts, improper construction, freeze-thaw cycles, and poor aggregate. Another recognized
source of distress is the reaction between the alkalies (Na20 and K20) in some cements and certaIn minerals in some 􀁡􀁧􀁾􀀠gates. Products formed 􀁾􀀠the reaction between the alkalies
and aggregate result in expansions that cause a breakdown in the concrete. This generally occurs-throughout the slab and not just at joints where "D" cracking normally occurs. Severity
Levels. a. Low severity level (L). Crazing or map cracKIng exists over 􀁭􀁯􀁳􀁾􀁦􀀠the slab area. the surface is in good condrtion with no scaling7 Note: The low severity level is an
indicator that scaling may develop in the future. b. Medium severity level approximately 5 percent or some loose 􀁾missing mat(M). less Slab is scaled over of the-surface with erIal:
􀁾􀀠High severity level scaled with a large amoumateriar:--Usually, more surface is affected. (H). nt--of than Slab is severely loose or missing 5 percent of the Counting procedure.
If two 􀁾􀁾levels of severity exist on .<:!: slab, 􀁾slab is counted 􀁾􀀠􀁾slab having the maximum level of severity. For example, if both low severity crazing and medium scaling exist
􀁾􀁾􀀠slab, the slab is counted as one slab 􀁣􀁯􀁮􀁴􀁡􀁩􀁮􀁾􀁮􀁧􀀠medium-SCaIIng.-----5-99 
􀁟􀁾􀁾􀁟􀁎________________􀁾__________________________________􀁾___􀁾______Airport Pavement Inspection by PCI Additional Criteria 1. Low severity is defined by map cracking/crazing.
The crack pattern must be well defined and easily recognized. Individual cracks should show some evidence of wear. Very early stages are ignored. The crack pattern must be evident over
more than 50 percent of slab surface. 2. Medium and high severity are rated by scaling. Medium severity means surface disintegration (scaling) is evident over five percent or less of
the slab. A rating of high severity requires that more than five percent of the slab surface be loose or missing. 3. Sun angle and moisture can change the appearance of map cracks significantly.
Use caution when recording map cracking on wet pavement surfaces. MAP CRACKING Figure 5-142 Cracks are well defined. No scaling has occurred. This is recorded as low severity distress.
5-100 
________ 􀁾􀁎􀁟􀁎_____ N ___________ N ____􀁾􀁾__ N ___________________􀁾_____ 􀁾__Airport Pavement Inspection by PCI \ I SCALING Figure 5-143 Figure 5-144 Loss of surface material represented
by Scaling. HIGH SEVERITY SCALING Figure 5-145 Figure 5-146 In Figure 5-146, map cracking is visible in the background with scaling at the near corner. Scaling and "D" cracking can have
similar appearance. Look for a pattern at lower severity elsewhere in the pavement. 5-101 
i 􀁟􀁾__N ______________N ___􀁾__________􀁾__􀁾______N _______􀁾_ __________􀁾􀁾􀁾􀀠Airport Pavement Inspection by PCI SETTLEMENT OR FAULTING -DISTRESS NO. 11. Standard Text. Description.
Settlement or faulting is a difference of elevation at a joint or crack -caused by upheaval or consolidation. Severity Levels. Severity levels are defined £l the difference in elevation
􀁡􀁣􀁲􀁯􀁳􀁳􀁾􀁨􀁥􀀠fault 􀁡􀁮􀁤􀁾􀁨􀁥􀀠associated decrease in ride -quality 􀁡􀁮􀁾􀁳􀁡􀁦􀁥􀁴􀁹􀀠as severity increases. Difference in Elevation Runways/Taxiways Aprons L .:: 1/4 in.
1/8 .:: 1/2 in. M 1/4 :: 1/2 in. ill -1. in. H 􀁾􀀠1/2 in. > 1 in. Counting Procedure. 􀁾􀀠counting settlement, a fault between two slabs is counted 􀁾􀁾slab. 􀀭􀁾􀀠straightedge or level
should be used to aid in measuring the difference in elevation-5etween 􀁴􀁨􀁥􀁾􀁷􀁯􀀠slabs. Additional Criteria 1. Construction induced elevation differential is not rated in PCI procedures.
2. Construction differential can only occur at a construction joint. Where construction differential exists, it can often be identified by the way the high side of the joint was rolled
down by finishers (usually within 6 inches of the joint) to meet the low slab elevation. Construction differential is quite common at longitudinal joints between paving lanes. 3. If
the slab which moved (up or down) can be identified by relative position of surrounding 5-102 
􀁾... NNN ___􀁎􀁎􀁎􀁎􀁎􀁎􀁎􀁾􀁟􀁎􀁎􀁎􀁎􀁎􀁎______N_NNN ____NN ______ 􀁾_______N _______N __􀁾__ Ni Airport Pavement Inspection by PCI \ slabs, rate the slab that moved. If positive determination
cannot be made, rate the low slab. \ I \ NO DISTRESS Figure 5-147 Figure 5-148 construction induced differential elevations do not represent vertical slab movement. SETTLEMENT OR FAULTING
Figure 5-149 Figure 5-150 5-103 I 
________ N _____________N ______________􀁾_________ 􀁎􀁟􀁾______________ 􀁾􀁟􀁾Airport Pavement Inspection by PCI SETTLEMENT OR FAULTING Figure 5-151 Figure 5-152 Measurement may be
made with a clipbOard straightedge. Settlement or Faulting are often emphasized by sealer or asphalt "skin patch" on the low side. Measurement must be from surface of one slab to surface
of the other. 5-104 
􀁾 N ____N i I \ I \ ____HN ___________________________________ ___________________Airport Pavement Inspection by PCI SHATTERED SLAB/INTERSECTING CRACKS-DISTRESS NO. 12 Standard Text.
Description. Intersecting cracks are cracks that break the slab into four ££ 􀁾pieces due tooverloading and7"Q:i?' inadequate support. The high severity level of this distress type,
􀁾defined below, is referred to as shattered slab. If all pieces or cracks are contained within a corner break, the -aistress is categorized 􀁾􀁾􀀠severe corner break; Severity Levels.
a. Low severity level (L). Slab is broken into four or five pieces with some or all-Cracks of low severity. b. Medium severity level (M). (1) Slab is broken into four or five pieces
with some or all cracks--of mediurn-Beverity. 􀁾Slab is broken into six or more pieces with all cracks of loWSeverity. 􀁾􀀠Hfgh severity.level (H). At this level of 􀁳􀁥􀁶􀁥􀁲􀁾􀁴􀁹􀀬􀀠the
slab :! called shattered. (1) Slab is broken into four or five pieces with some or all cracks of high severIty. (2) Slab is broken into six or more pieces with some or all cracks Cif'
mediumor high sever 'i'tY7 Counting Procedure. If 􀁾􀀠slab is rated as medium or 􀁾􀁩􀁧􀁨􀀠severity level shattered slab, 􀁾􀁾other 􀁤􀁾􀁳􀁴􀁲􀁥􀁳􀁳􀀠type should be counted in the slab.
The deduct values for Shattered slab dIStress are high since this condI= tion is essentially failure; therefore, the counting of other distress types in the slab woUld tend 􀁾􀀠underrate
the PCI of the sample unit. Additional Criteria 1. The title of this distress type tends to create confusion. We use the term "segmented slab" to 5-105 i 
_N __ 􀁾􀁾_____________________ 􀁾__􀁾___________􀁾__ 􀁾􀁟􀁾_____􀁾_____________Airport Pavement Inspection by PCI define slabs rated at low and medium severity. A segmented slab is
not a shattered slab. 2. To be rated at low severity, all defining cracks must be at low severity. 3. Cracks must separate the pavement into segments. Count only L/T/D cracks. Corner
breaks do not identify a segment for evaluating this . 1 distress type. 5. If a segmented slab is rated at medium severity, no other distress types on that slab are recorded. LOW SEVERITY
SEGMENTED SLAB Figure 5-153 Slab is divided into 5 pieces by low severity cracks. (Pieces smaller than one foot wide are not counted.) 5-106 
􀁎􀁾􀁟􀁎_____N ______NN ____________________________________􀁾__􀁎􀁟􀁾______ _Airport Pavement Inspection by PCI \ 1 I \ i I I MEDIUM SEVERITY SEGMENTED SLAB Figure 5-154 Figure 5-155
Slab at Figure 5-154 is divided into 4 pieces (one crack has been graphically enhanced), but one crack is at medium severity (wider than 1/8 inch.) Figure 5-155 shows defining cracks
at medium severity . . 1 SHATTERED SLAB Figure 5-156 Figure 5-157 Slab in Figure 5-156 has more than 6 pieces. Slab in Figure 5-157 is divided by high severity cracks. 5-107 I 
􀁾􀁾􀁟􀁾􀁟􀁾____________N ____________________________􀁾____Airport Pavement Inspection by PCI SHRINKAGE CRACKS -DISTRESS NO. 13. Standard Text. Description. Shrinkage cracks 􀁾􀀠hairline
cracks that are usually only 􀁾􀀠few feet long and do notexteiid across the entire slab. They 􀁾formed during the setting and curing of the concrete and usually do 􀁾extend through the
depth of the slab. Severity Levels. No degrees of severity are defined. It is sufficient to indicate that shrinkage cracks exist: Counting Procedure. If one or more shrinkage partICular
sIai), the slab is with shrinkage cracks. cracks counted exist on as one one slab Additional Criteria 1. The single criterion for identification of a shrinkage crack is that it does
not extend full width of a slab. A crack that intersects two joints of a slab is a corner break, L/T/D crack or spall. 2. Shrinkage cracks are formed at time of construction and will
therefore be weathered and covered by any debris or stains on the surface. Shrinkage cracks do not not have internal movement and, therefore, will not "cut" through a stain or rubber
mark from a tire. Fresh new cracks and working cracks are not shrinkage cracks. 5-108 
􀁾􀁾􀁾____ 􀁾􀁎________ 􀁎􀁟􀁾􀁾________________________􀁾􀁟􀁎__ 􀁾􀁟Airport Pavement Inspection by PCI \ .. Figure 5-158 Figure 5-159 Figure 5-160 SHRINKAGE CRACKS The above figures
present typical examples of Shrinkage Cracks. 5-109 
Airport Pavement Inspection by PCI􀁎􀁎􀁾􀁾􀁟􀁾􀁎􀁾􀁾􀁎􀁟􀁎􀀠􀁎􀁎􀁟􀁎􀁎􀁟􀁎􀁎􀁾􀁎􀁎__ 􀁾______ ___ ___ 􀁎􀁟􀁎􀁎􀁟􀁎􀁟􀁾__ NN_N N_N _N__________ SPALLING (TRANSVERSE AND LONGITUDINAL JOINT)
DISTRESS NO. 14. Standard Text. Description. Joint spalling is the breakdown of the slab 􀁥􀁤􀁾􀁥􀁳􀀠within 􀁾􀀠ft of the side of the joint. !! 􀁪􀁯􀁾􀁮􀁴􀀠spall usually does 􀁾􀀠extend
vertically through the slab but intersects the joint at 􀁾􀀠angle. Spalling results from excessive stresses 􀁾􀀠the joint 􀁾􀀠crack caused £i infiltration of !ncompressible materials
or traffic load. Weak concrete at the joint (caused by overworkIngf combined with traffic loads is another cause of spalling. Severity Levels. a. Low severity level (L). ill Spall 􀁾􀁾􀀠ft
long: (a) Spall is broken into no more than three pieces defined £i low ormediuiii severity cracks. (b) Joint is lightly frayed either with little, if any, loose or missing material.
(2) Spall less than 2 ft long is broken into :pieces or rragmeiited -with -rITtle loose-or missing material 􀁾􀀠tire damage potential. b. Medium severity level 􀁾􀀠ill Spall 􀁾􀁾􀀠ft
long: (a) Spall is broken into more than three :pieces defined by 􀁬􀁩􀁧􀁨􀁾􀀠medfum-cracks. (b) Spall is broken into no more than three pieces with one or more--oI the cracks being
􀁳􀁥􀁶􀁥􀁲􀁥􀀭􀀭􀁗􀁩􀁴􀁾􀀠some loose-or missing material. (c) Joint is moderately frayed with some IOOse 􀁾missing material. (2) Spall less than 􀁾􀀠ft long is broken into 􀁾􀀠􀁰􀁾􀁥􀁣􀁥􀁳􀀠or
fragmented with 􀁾of the pieces 5-110 
\ ___NN ____N ___􀁾__N ___________􀁾_________________________􀁾___________ _Airport Pavement Inspection by PCI loose or absent with 􀁾tire damage poten􀁴􀁾􀁡􀁬􀀮􀀠c. High severity level
(H). Spall over 􀁾􀀠ft long: (1) Spall is broken into more than three 'j?Ieces defined !:!x one or more high severity cracks with high possibility of the pieces becoming dislodged. (2)
Joint is severely frayed with a large amount of loose 􀁾missing particles. Note: If less than 2 ft of the joint is lightly frayed, 􀁴􀁨􀁥􀀭􀁳􀁰􀁡􀁬􀁲􀀭􀁳􀁨􀁯􀁵􀁬􀁾􀁮􀁯􀁴􀀠be counted.
Counting procedure. If the joint spall is located along the edge of 􀁾􀀠􀁳􀁲􀁡􀁾􀁩􀁴􀀠is counted 􀁾􀀠􀁾􀀠slab with 􀁪􀁯􀁾􀁮􀁴􀀠spalling. If spalling is located 􀁾􀁾than one edge of the
􀁾slab, the edge having the highest severity is counted and recorded 􀁾􀀠one slab. Joint spalling 􀁾also occur along the edges of two adjacent slabs. If this is the case, each slab is
counted 􀁾having jOint spalling. Additional Criteria 1. AC 150/5380-6 presents conflicting information related to low severity joint spalls. The definitions and photographs associated
with the description at page B-85 and B-86 of AC 150/5380-6 seem clear, but specific action for this condition given at Table B-1, page B-3, suggests otherwise. We have given precedence
to Table B-1. Minor fraying or spalling of a joint edge does not reduce serviceability of pavement any more than a filled core hole, single popout or surface texture blemish. The examples
given in photographs Figure B-129 and B-130 on page B-86 show jOint spalling and jOint fraying that can be filled during a jOint seal repair and should not be recorded. 2. Any frayed
edge or chip within three inches of a joint, measured from the opposite jOint edge, should not be recorded. 3. Lightly frayed refers to a process where individual stones and particles
are dislodged and worn 5-111 
􀁾􀁎________ 􀁾􀁎􀁾_____________ 􀁾________________________􀁾_____________ 􀁾􀁟Airport Pavement Inspection by PCI . I . I away by traffic as opposed to a chunk of pavement being broken
away. Lightly frayed joints are less than 3 inches wide measuring from opposite joint edge as described above. A moderately frayed joint exceeds three inches from opposite joint edge.
A severely frayed jOint edge exceeds six inches from opposite joint edge. Moderate and severe frayed edges normally result from spalls from which all material is missing. 4. Normally,
both ends of the boundary crack of a joint spall will intersect the same joint. However it is possible for a joint spall to terminate at a slab corner. The following criteria are used
to identify joint spalls terminating at slab corners. All three conditions are necessary. a. The spall length is at least five times greater than the spall width. b. The spall width
is less than one foot. c. The spall length is greater than two feet. NO DISTRESS Figure 5-161 Figure 5-162 Spalls presented in Figures 5-161 and 5-162 are less than 3 inches wide. 5-112

􀁾􀁾􀁾______􀁾____ 􀁾__ N _______􀁾___􀁾_____􀁾________􀁾􀁾_____________ 􀁾______ _Airport Pavement Inspection by PCI \ \ I \ I LOW SEVERITY JOINT SPALLS Figure 5-163 Figure 5-164 LOW
SEVERITY JOINT SPALLS Figure 5-165 Figure 5-166 The crack defining the spall at Figure 5-165 has not yet connected to the joint. but tapping on the area between the crack and the joint
gives a hollow sound indicative of failure. Spall at Figure 5-166 is less than 2 feet long and presents no tire damage potential. . I . 5-113 
Airport Pavement Inspection by PCI MEDIUM SEVERITY JOINT SPALL Figure 5-167 HIGH SEVERITY JOINT SPALL Figure 5-168 Spall at Figure 5-167 is longer than 2 feet, defined by a high severity
crack. Although the crack has not connected to the joint, the space between has failed. JOINT SPALLS AT SLAB CORNER Figure 5-169 Figure 5-170 These spalls meet special criteria at page
5-112 for joint spalls which intersect slab corners. 5-114 
___N ________ N _____________________________________________________Airport Pavement Inspection by PCI _ SPALLING (CORNER) -DISTRESS NO. 15. Standard Text. Description. 􀁣􀁯􀁲􀁮􀁥􀁲􀀮􀁳􀁰􀁾􀁬􀁬􀁩􀁮�
�􀀠is 􀁾􀁨􀁥􀀠raveling or breakdown of the slab 􀁷􀁾􀁴􀁨􀁾􀁮􀀠􀁡􀁰􀁰􀁲􀁯􀁸􀁾􀁭􀁡􀁴􀁥􀁬􀁹􀀠􀁾􀀠ft of the corner. A corner spall differs from a corner break in that the spall usually angres-doWnward
to intersect the joint, while a break extends vertically through the slab. Severity Levels. a. Low severity level (L). One of the following condItfons exists: (1) Spall is broken into
one or two pieces defined by low severity-crackS7 Pieces-are not easily dislodged. (2) Spall is defined Ex 􀁾medium severity crack with the material secured in place. b. Medium severity
level One of the fOllowing conditions exists: (1) Spall is broken into two or more pieces defined by medium seve:rrt:'Y crack(S), and 􀁾􀀠few small fragments may be absent 􀁾􀀠loose.
(.2) spall is defined Ex 􀁾severe, fragmented crack that may be accompanied Ex 􀁾􀀠few hairline cracks-.-(3) Spall has deteriorated to the point where IOOse materiar-exists. c. ¥igh
severity level (H). One of the following 􀁣􀁯􀁮􀁤􀁾􀁴􀁩􀁯􀁮􀁳􀀠exists: (1) Spall is broken into two or more pieces defined by hIgh severItY 􀀭􀁲􀁲􀁡􀁧􀁭􀁥􀁮􀁾􀁣􀁲􀁡􀁣􀁫􀀨􀁳􀀩􀀠with loose
􀁾absent fragments. (2) Pieces of the spall have been displaced to the extent that 􀁾􀀠tire damage haZard exists. Counting Procedure. If one or more corner spalls having the sarne 5-115

Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭severity level
are located in a slab, the slab is counted 􀁾􀁾slab with corner-spa11ing:-If more than 􀁾severity level occurs, it is counted as 􀁾slab having the higher severity level. Additional Criteria
1. A corner spall smaller than three inches wide, measured from the opposite joint edge, is not recorded. Otherwise, the size of a spall is not a factor in rating severity. 2. The ends
of the boundary crack of a corner spall must intersect at perpendicular joints which form a corner of the slab. 3. Loose and missing materials within three inches of a joint, measured
from the opposite joint edge, are ignored when rating a spall. 4. In rating, there is no distinction between loose and missing material in a spall. Pieces which cannot be easily dislodged
are not loose pieces. 5. A fragmented crack is actually two or more cracks in close proximity proximity which meet below the surface forming a single channel to subbase. The multiple
cracks are interconnected to form small fragments, or pieces, of pavement. 6. If more than ten percent of the spalled surface is loose or missing, excluding loose areas within three
inches of a joint measured from the opposite joint face, the spall is rated at high severity. NO DISTRESS Figure 5-171 Distress is less than 3 inches wide. 5-116 
􀁟􀁎􀁾􀀠i I \. I I \ i . i 􀁾􀀠􀁾􀀠􀁾 __________ _____ N _____________________________________ ___ ____ _Airport Pavement Inspection by PCI LOW SEVERITY CORNER SPALLS Figure 5-172 Figure
5-173 Loose pieces in the spall at Figure 5-173 are all contained within 3 inches of the corner. MEDIUM SEVERITY CORNER SPALLS Figure 5-174 Figure 5-175 5-117 
'.! 
_____ 􀁎􀁟􀁾____________N ______N ________________________________________Airport Pavement Inspection by PCI \ 􀁃􀁾􀁐􀁔􀂣􀁒􀀶􀀠DRAINAGE CONDITION INDEX PROCEDURES CONCEPT Drainage Condition
Index (DCI) is an indicator of the impact uncontrolled moisture has on pavement condition. parameters are chosen to indicate drainage conditions according to their impact on pavement
serviceability. Each parameter is defined, and measuring procedures are described, so that consistent results are possible during field inspection. The DCI technology described here
has been developed to closely parallel Pavement Condition Index (PCI) technology. Selected pavement sample units are examined, and pavement features are rated, using identical layout
procedures prescribed for PCI. Drainage condition indicies range from 100 to 0, and are calculated by deducting points from 100 for drainage condition indicators according to impact
and severity. Drainage Condition Indicators are easily identified. and can be readily measured and rated. Deduct values are calculated for each indicator by severity and according to
impact on pavement condition. Since DCI will be implemented in conjunction with (PCI), the DCI technology was developed so that data may be collected simultaneously during a PCI survey.
PCI distress conditions caused, or aggravated, by poor drainage are used as DCI condition indicators. Several additional parameters are defined to assure comprehensive representation
of drainage conditions, but expensive and time consuming techniques, such as coring, laboratory testing and elaborate analytical computer models are not used in the data collection and
rating process. 6-1 
__N ___􀁾__N ______N _____N __􀁾􀀠__________􀁾􀁎_______________􀁾______________Airport Pavement Inspection by PCI INDICATORS DRAINAGE PARAMETERS The following drainage parameters are
measured and rated to establish a Drainage Condition Index for airport pavement systems. SLOPE TO SHOULDER (INLET). -DISTRESS NO. Dl. Description. Gradient on pavement to expedite runoff
is largely a matter of safety and appearance. The affect of standing water on pavement serviceability is minimal. However, the amount of water that can infiltrate to subgrade from cracks
in the surface is increased as rate of runoff decreases. Transverse slope on a runway or taxiway, and slope to edge or drainagestructure on an apron, establish the rate at which water can run off the pavement surface. A good rate of runoff is desirable to minimize the time of exposure of the pavement structure
to infiltration. Severity Levels. 􀁾􀀠Low Severity Level (L). Slope is less than one percent but more than one half percent. 􀁾􀀠Medium Severity Level (M). Slope is one half percent
or less but more than flat. c. High severity Level TPonding is evident). 􀁾􀀠Slope is flat or negative Measuring Procedure. One measurement is made for each 2000 square feet of sample
unit area. Measurements are made along a ten foot horizontal distance. Points of measurement are selected within a sample unit to represent typical, or average, slope conditions. On
taxiways and runways, at least one measurement is made each side of centerline. On aprons, at least one measurement is made in each quadrant approaching a drainage structure and one
measurement is made toward each pavement edge. The average of measurements in a sample unit is used to establish severity level. Measurements are made to the nearest 0.1 percent. 6-2

_________ _____________ _________________________________________ _ 􀁾􀁎􀁾􀀠􀁾􀀠Airport Pavement Inspection by PCI \ , :j Slope Measurement on Pavement Figure 6-1 Slope measurements
are used to establish severity unless ponding water, or ponding stains, are evident to the inspector. Evidence of ponding water on less than one quarter of the surface results in a minimum
rating of medium severity (slope measurements are recorded). Evidence of ponding water over one quarter or more of the surface results in a rating of high severity ponding Water (slope
measurements need Figure 6-2 not be made). SHOULDER SLOPE. -DISTRESS NO. D2. Description. Shoulder slope away from pavement edge is important to assure that surface runoff water is transported
away from the pavement substructure. If shoulders are flat, or if reverse slope exists, water will soak into and saturate shoulder soil, limiting potential for subsurface moisture to
drain away from the structure, ultimately softening subgrade and reducing load capacity of of the pavement. 6-3 
􀁾􀀠􀁾􀀠 􀁾􀀠􀁾 N _____________ _________ _______________ _________ _________________Airport Pavement Inspection by PCI severity Levels. a. Low Severity Level (L). Slope is less than
three percent but more than one and one half percent. b. Medium Severity Level (M). Slope is one and one half percent or less but more than flat. 􀁾High Severity Level (H). Slope is
flat or negative. Measuring procedure. Slope is measured from ground level at pavement edge to a point ten feet from pavement edge. Measurements are made along a ten foot horizontal
distance. Where the shoulder is uneven on the line of measurement, the mean slope in the ten foot distance is recorded. Care must .J be used to establish ground level at pavement edge.
Buildups of dead grass or loose sand should be cleared away before measurements are taken. These parameters, and washouts adjacent to pavement, are accounted for in the following distress,
"Shoulder Condition". Measurements are made to the nearest 0.5 percent. Measuring Shoulder Slope Figure 6-3 SHOULDER CONDITION. -DISTRESS NO. D3. Description. Shoulder condition at edge
of pavement is an important drainage parameter. Turf and incompressibles washed 6-4 
_NNNNNN____NN _____􀁾􀁾__________________________________􀁾____ 􀁾________Airport Pavement Inspection by PCI \ from the surface may build up over time to create an effective "dam" against
runoff. On the other hand, ifi runoff water has eroded the shoulder at pavement edge, a I trench may be formed which catches and funnels water inI to the subgrade. In either case, water
will be trapped I and will gradually infiltrate into the subgrade and reI duce bearing capacity of the pavement. Shoulder Condition Built up Edge Damaged Shoulder Figure 6-4 Figure 6-5
Severity Levels. 􀁾Low Severity Level 􀁾􀀠Shoulder within one foot of pavement edge generally permits unrestricted runoff with exception of dam or trench capable of holding ponded water
along no more than ten percent of its length. 􀁾􀀠Medium Severity Level (M). Shoulder within one foot of pavement edge is dammed-or-trenched sufficiently to hold ponded water over more
than ten percent but less than 50 percent of its length. c. High Severity Level (H). Shoulder within one foot or pavement edge is dammed or trenched sufficiently to hold ponded water
over more than 50 per cent of its length. 6-5 
􀁾􀀠􀁾􀀠􀁾 ___N ___________________________ ____________________ _ _____ ________ Airport Pavement Inspection by PCI Measuring Procedure. Grass stems and loose sand at pavement edge
do not restrict runoff unless they become mixed with soil (mud) or other impervious materials to form a dam. A trench is evidenced by flat or negative slope within one foot of pavement
edge. Unrepaired tire ruts in shoulder within one foot of pavement edge are measured to establish severity. Tightly woven turf (grass root mass at pavement edge) will hold ponded water
and is measured to establish severity. An effective technique for determining degree of shoUlder "damming" is to walk along the pavement edge. Damming is indicated if ankles tend to
rotate toward the pavement side. Shoulder Condition Measuring Technique Figure 6-6 INLET CONDITION Description. Inlets and catch basins are normally found in large expanses of pavement
as at aprons. They are designed to remove surface water from the paved surface more expeditiously than runoff to shoulders will allow. Any condition which prevents an inlet from accepting
runoff from the pavement is a distress. Distress can range from joint seal damage around the inlet, to lifting or settlement of the structure relative to surrounding pavement, to debris
in grates and catch basins, to sludge in catch basins, to physical deterioration of inlet grates, 6-6 
Airport Pavement Inspection by PCI 􀁾􀀭􀀭􀀭􀁾􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭structure or
associated storm drains. Severity of inlet distress is related to degree of flow restriction (Flow Rate -Distress No. D4) and condition of structure (Structural -Distress No. D5). Measuring
Procedure. Only inlets constructed in, or within ten feet of, rated pavement are rated. Rate all inlets in rated pavement. Include trench-type as well as box inlets. Flow Rate -DISTRESS
NO. D4. Severity Levels. Low Severity Level (L). Distress is limited to condition{s) correctable by staff maintenance, such as debris in grates or catch basins. Low and medium severity
joint seal damage at perimeter of structure constitutes low severity inlet flow distress. or settlement of one quarter inch severity distress. Structural faulting or less is a low Medium
Severity Level (M). High severity perimeter joint seal damage constitutes medium severity distress. Structural faulting or settlement greater than one quarter inch but less than one
inch is rated at medium severity. Sludge at bottom of catch basin less than one forth the depth of the smallest diameter connecting storm drain constitutes medium severity distress.
(Mud or sludge at or below flow line of the lowest outlet is not considered in rating inlets). High Severity Level (H). Examples of high severity distress include: 􀀨􀁬􀁾􀁵􀁤􀁧􀁥􀀠in
bottom of catch basin (not debris induced) deeper than one quarter of the depth of the smallest diameter connecting storm drain. (2) Structural faulting or settlement of one inch or
greater. Structural -DISTRESS NO. D5. Severity Levels. Low Severity Level (L). Inlet and structure are generally serviceable. Distress is limited to condition(s) correctable by staff
maintenance, such as tuck pointing masonry and grouting small cracks in structure walls. Cracks in catch basin walls or floor one eighth inch wide or less with no faulting at cracks
constitutes low severity distress. Mortar damage in block walls is a low severity distress if blocks are securely in place. 6-7 
__ 􀁾􀁟􀁎_________ 􀁾___ 􀁾_________________________􀁾􀁟􀁾_____________________Airport Pavement Inspection by PCI Medium Severity Level (M). Distress is correctable without major structural--rehabili
tation, such as a broken inlet grate or cracked and faulted structure slabs. Cracked catch basin walls or floor less than one half inch wide with faulting less than one half inch constitutes
medium severity distress. Mortar damage in masonry walls resulting in voids between blocks, with some blocks loose but not broken or displaced is a medium severity distress. Any movement
of inlet casting under body weight of the inspector constitutels medium severity distress. High Severity Level (H). Correction of distress requires major structural rehabilitation. Examples
of high severity distress include: (1) Shattered structure slab with missing pieces and faulting of one inch or . I more; (2) Shattered walls or floor of catch basins with I multiple
cracks of one half inch or more and faulting at cracks of one half inch or more; (3) Missing pieces from walls or floor exposing reinforcing steel and mesh; (4) Broken or displaced masonry
blocks in the structure. PCI DISTRESS PARAMETERS Several distress types used for rating PCI contribute to uncontrolled moisture conditions in the pavement structure. These distress types
become drainage condition indicators for establishing DCI. They include: Flexible Pavement Depressions Rutting Alligator Cracking Block Cracking Reflective Cracking Longitudinal, Transverse
Cracking Rigid pavement Longitudinal, Transverse, Diagonal Cracking Settlement or Faulting Pumping Joint Seal Damage Shattered Slab PAVEMENT STRUCTURE PARAMETERS Pavement components
and subgrade are very important parameters in rating drainage impact. Underdrains installed under, or adjacent to, a runway, taxiway or 6 
---I NN ____________________________________________________________ 􀁾____ _Airport Pavement Inspection by PCI \ \ apron also contribute substantially to control of moisture which,
in turn, reduces the impact on pavement condition. Drainage condition indicators related to materials in the pavement and subgrade, and underdrain systems include: Base Course Type Subbase
Type Subgrade Type Underdrain System DATA COLLECTION PROCEDURES Records research of pavement history yields information on underdrains, and base course, subbase and subgrade types, in
addition to traditional historical information. PCI distress conditions used for calculation of DCI are retrieved from PCI file data. Pavement slope and shoulder slope of inspected sample
units are measured. Measurements may be made with a ten foot straightedge and a carpenters level. The straightedge is placed on pavement or shoulder at desired point of measurement.
The low end is raised until the pipe is level (demonstrated by a level bubble). The distance from from surface is measured in tenths of feet and recorded. This measurement directly translates
to percent slope. Shoulder condition and inlet condition are rated based on descriptions given. Surveyors inspect shoulder condition of sample units inspected, and all inlets in rated
pavement. CALCULATION OF DCI Deduct points are calculated for each measured drainage parameter based on severity of distress. If a parameter meets the established standard, there is
no deduct. If underdrains are installed at pavement edges, deduct values are reduced. The reason is that, for most of the year, edge drains help to control moisture in shoulder soil.
However, at critical periods in the spring, the drains may be below frost line and ineffective. When this condition occurs, elements above frost line perform 6-9 
. i I I ! I Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀁾􀀭􀁾􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭as
if without underdrains. Shoulder condition is a critical condition in that water trapped adjacent to edge of runway invariably filters back under pavement to subgrade. The condition
is much less serious if underdrains are installed along pavement edges. Inlet deterioration reduces capacity of an underground storm drain system and often allows direct access of surface
water into subgrade. Separate deducts are calculated for flow restrictions, and for structural deterioration. Drainage deducts for rated PCI distress types are calculated as a function
of total PCI deduct. Deduct factors reflect the relationship of drainage to each rated PCI distress type. Pavement and subgrade materials are acted on by uncontrolled moisture. They
are the reason drainage is important. consequently, base course, subbase course and subgrade are factored into DCI calculations in a different manner than other condition indicators.
As quality of material in each of these components improves, the impact of uncontrOlled moisture is reduced. Therefore, the Total Deduct Value (TDV) , the sum of deducts from parameters
described above, is reduced by a factor related to the quality of pavement components and subgrade. Underdrains are a primary means of controlling moisture in a pavement structure, and
in subgrade. They allow continuous drainage of water from base and subbase courses in pavement, and they effectively lower the water table in subgrade, helping to stabilize and strengthen
the foundation material. Correction factors for a broad range of types and classes of base course, subbase course and subgrade, with and without underdrains, are calculated. COMPUTER
EVALUATION Eckrose/Green AIRPAV programs are outlined in Chapter 2. Drainage conditions are fully integrated into the AIRPAV software. DCI minimum service levels are assigned, costs
for maintenance and rehabilitation actions are 6-10 
N __ N ____􀁾__ N _______􀁾____ N ______ N ______________􀁾_______ ______________Airport Pavement Inspection by PCII estimated, and corrective actions are incorporated into AIRPMS Master
File and AIRCIP modules. Pavement rehabilitation actions presented in the Master File correct drainage conditions to varying degrees. For instance, a "Reconstruction" alternative in
flexible I or rigid pavement corrects all drainage deficiencies and \ restores DCI to 100. Other alternatives improve DCI to a lesser degree by correcting specific rated deficiencies.
"Structural Overlay" in flexible pavement, and "Reseating/overlay" in rigid pavement, correct pavement slope deducts. Structural overlay, Reseating/Overlay, and "Resurfacing", also correct.
all PCI distress and inlet flow deducts, but do not effect inlet structural, shoulder, pavement materials, or subgrade deducts. A corrected DCI value, based on any of the above rehabilitation
options, is presented in the Master File to show degree of improvement. In addition to pavement actions, six drainage actions are evaluated in the Management Program and presented in
the Master File. They are: Shoulder Grading (slope) Shoulder Grading (condition) Underdrains Inlet (flow) Inlet (structure repair) No Action Each of these actions may be performed independently
from pavement actions to improve drainage conditions. These actions are presented in the Master File with cost estimates and corrected DCI values. They are also presented in the AIRCIP
Capital Improvements module, and may be integrated into capital improvement and maintenance programs for an airport. 6-11 
-.-1 I 
--------------------------------------------------------------I I \ \ Airport Pavement Inspection by PCI DRAINAGE CONDITION INDEX PROCEDURES ADDITIONAL CRITERIA Underlined text is reproduced
as.it appears in Chapter 6 of the manual "Airport Inspection by PCI". Additional criteria are added following each distress description and measuring procedure. SLOPE TO SHOULDER (INLET).
-DISTRESS NO. D1. Description. Gradient on pavement to expedite runoff is largely 􀁾􀀠matter of safety and apPearance. The affect of standing water 2n pavement serviceability is minimal.
However, the amount of water that £Sn infiltrate to subgrade from cracks in the surface is increased as rate of runoff decreases. Transverse slope 2n 􀁾􀀠runway or taxiway, and slope
to edge 􀁾􀀠drainage structure Qn an apron, establish the rate 􀁾􀀠which water can run off the pavement surface. 􀁾􀀠good 􀁾of runoff is desirable to minimize the time of exposure of
the pavement structure to infiltration. Severity Levels. !h. Low Severity Level.ib.L... Slope is less than one per􀁾but more than one half percent. . 􀁾􀀠Medium Severity Level 􀁾􀀠Slope
is 􀁾half percent 􀁾􀀠less but 􀁾than flat. 􀁾􀀠High severity Level 􀁾􀀠Slope is flat 􀁾negative (ponding is evident). Measuring Procedure. One measurement 􀁾made for each 2000 square
feet of sample unit area. Measurements 􀁾made along 􀁾􀀠ten foot horizontal distance. Points of measurement 􀁾selected within 􀁾􀀠sample unit to represent typical, 􀁾􀀠average. slope
conditions. On taxiways and runways, 􀁾􀀠least 􀁾measurement 􀁾􀀮􀁭􀁡􀁤􀁥􀀠each side of centerline. Qn aprons, 􀁾􀀠least 􀁾measurement is made in each guadrant approaching 􀁾􀀠drainage
structure and 􀁾measurement is made toward each pavement edge. The average of measurements in 􀁾􀀠sample unit is used 1Q establish severity level. Measurements 􀁾made to the nearest
0.1 percent. 1 
-. 􀁾􀀠'I ______ N __________ 􀁾____________________________________ ________Airport Pavement Inspection by PCI Slope measurements 􀁾used 􀁾􀀠establish severity unless ponding water,
􀁾􀀠ponding stains, 􀁾evident to the inspector. Evidence of ponding water £n less than 􀁾􀀠guarter of the surface results in 􀁾􀀠minimum rating of medium severity (slope measurements
􀁾recorded). Evidence of ponding water over 􀁾quarter 􀁾􀁾of the surface results in 􀁾􀀠rating of high severity (slope measurements need not be madel. Additional Criteria. 1. Slope measurements
are recorded, on taxiways and runways, according to location left or right of centerline. Measurements on aprons are not recorded by location. 2. Slope measurements are recorded as positive
in direction of designed flow. A superelevated pavement, for instance, has positive slopes, even though runoff is across centerline. 3. Slope on apron pavement is measured in the direction
of maximum slope (to establish the direction of flow of surface water). On some aprons, this direction will be obvious. Where direction of flow is in question, the inspector should make
several slope measurements in a representative area. The maximum slope in a representative area is recorded. The term "maximum slope" refers only to measurements in a representative
area of the sample unit. The inspector is responsible to establish a representative slope(s) for the sample unit. If pavement contour is variable, several areas should be measured to
assure accurate representation. Record the maximum slope in each area. 4. "Ponding" is a difficult distress to quantify. When water or stains are present, ponding is evident, but the
area must be determined. Ponding may also be evidenced by depressions, but can exist where depressions are not recorded. Ponding potential may be identified by reverse slopes in a sample
unit. Once the dominant direction of slope has been established, a negative slope indicates ponding potential. Time consuming and precise measurements are not required. It is only necessary
to establish that ponding may exist (requires medium severity rating), then whether it exists over more than 25 percent of the sample unit area (requires high severity rating). Record
medium severity ponding with a 0.05 slope. Record high severity ponding with a -10 slope. These values will be indicators, on data sheets, of ponding. 5. Disregard depressions and ponding
areas smaller than 250 square feet. 2 I 
I Airport Pavement Inspection by PCI \ -------------------------------------------------------------\ \ \ SHOULDER SLOPE. -DISTRESS NO. D2. Description. Shoulder slope away from pavement
edge is important to assure that surface runoff water is transported away from the pavement substructure. If shoulders 􀁾flat. 􀁾􀀠if reverse slope exists. water will soak into and saturate
shoulder soil. limiting potential for subsurface moisture to drain away from the structure. ultimately softening subgrade and reducing load capacity of the pavement. Severity Levels.
􀁾􀁾Severity Level 􀁾Slope is less 􀁾three percent but !!l.2.!.!l.. than 􀁾and one half percent. 􀁾􀀠Medium Severity Level 􀁾􀀠Slope 􀁾􀁾and 􀁾half percent or less but more than flat.
􀁾􀀠High Severity Level 􀁾􀀠Slope is flat 􀁾􀀠negative. Measuring Procedure. Slope is measured from ground level 􀁾􀀠pavement edge to a point ten feet from pavement edge. Measurements
are made along a ten foot horizontal distance. Where the shoulder is uneven on the line of measurement, the 􀁾slope in the ten foot distance is recorded. Care must be used 􀁾􀀠establish
ground level at pavement edge. Buildups of dead grass 􀁾􀀠loose sand should be cleared away before measurements 􀁾􀀠taken. These parameters, and washouts adjacent to pavement, are accounted
for in the following distress, "Shoulder Condition". Measurements 􀁾made 􀁾􀀠the nearest 0.5 percent. Additional Criteria. 1. Shoulders affect pavement condition within a relatively
short distance from pavement edge (perhaps five feet). On taxiways and runways, this is a significant percentage of the total pavement area. Aprons, on the other hand, are normally more
rectangular in shape, and the pavement edges are relatively insignificant. Consequently, shoulder slopes adjacent to aprons are not rated. 2. Shoulders in confined areas, as at hangar
taxiways, and near buildings, are often designed sloping toward pavement. The inspector should recognize such landscaped shoulders as having an "architectural" rather than a "drainage"
function. Such shoulders should be recorded as N/R (not rated). 3 
Airport Pavement Inspection by PCI 􀀭􀀭􀀭􀀭􀁾􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭􀀭SHOULDER CONDITION. -DISTRESS
NO. 03. Description. Shoulder condition 􀁾􀀠edge of pavement is 􀁾􀀠important drain􀁾parameter. Turf and incompressibles washed from the surface may build 􀁾􀁾time tQ create 􀁾􀀠effective
"dam" against runoff. On the other hand, if runoff water has eroded the shoulder at pavement edge. 􀁾􀀠trench may be formed Which catches and funnels water into the subgrade. 􀁾􀀠either
case. water will be trapped and will gradually infiltrate intQ the subqrade and reduce bearing capacity of the pavement. Severity Levels. 􀁾Low Severity Level 􀁾􀀠Shoulder within one
foot of pave􀁾edge generally permits unrestricted runoff with exception of'dam 􀁾􀀠trench capable of holding ponded water along llQ 􀁾than ten percent of its length. 􀁾􀀠Medium Severity
Level 􀁾􀀠Shoulder within 􀁾foot of pavement edge is dammed 􀁾,trenched sufficiently to hold hold ponded water 􀁾􀁾than t.!Ul. percent but less than 􀁾􀀠percent of its length. 􀁾􀀠High
Severity Level 􀁾􀀠Shoulder within 􀁾􀁾of pavement edge is dammed or trenched sufficientlv to hold ponded water 􀁾􀁾than 50 per cent of its length. Measuring Procedure. Grass stems and
loose sand at pavement edge do not restrict runoff unless they become mixed with soil (mud) 􀁾􀀠other impervious materials to form 􀁾􀀠dam. A trench is evidenced Qy flat 􀁾􀀠negative
slope within 􀁾􀁾of pavement edge. Unrepaired tire ruts in shoulder within 􀁾foot of pavement edge are measured tQ establish severity. Tightly woven 􀁾􀀠(grass 􀁾􀁾􀁾􀀠pavement edge)
will hold ponded water and is measured to establish severity. An effective technique for determining degree of shoulder "damming" II tQ walk along the pavement edge. Damming is indicated
if ankles tend to rotate toward the pavement side. Additional Conditions. {See additional criteria for Distress No.2, above. l 4 
I Airport Pavement Inspection by PCI -------------------------------------------------------------\ INLET CONDITION \ Description. Inlets and catch basins 􀁾normally found in large expanses
of pavement as at aprons. They 􀁾designed to remove 􀁾􀀠face water from the paved surface 􀁾expeditiously than runoff to shoulders will allow. Any condition which prevents an inlet from
accepting runoff from the pavement is 􀁾􀀠distress. Distress can range from joint seal damage around the inlet. to lifting 􀁾􀀠settlement of the structure relative 􀁾􀀠surrounding pavement.
to debris in grates and catch basins. to sludge in catch basins. to physical deterioration of inlet grates, structure 􀁾􀀠associated storm drains. Severity of inlet distress is related
to degree of flow restriction (Flow 􀁾􀁾􀀠Distress No. D4l and condition of structure (Structural 􀁾􀀠Distress No. 􀁾􀀠Additional Criteria. 1. Only surface distress at inlets is rated.
This is a modification of rating procedures, and will be incorporated into the text at at next revision. The change is effective April 1, 1989, but will only be implemented on contracts
in effect on that date with prior concurrence of the Client. Ratings of interior conditions have not proved to be quantifiable. Once runoff water enters an inlet, it is no longer a threat
to pavement components and subgrade. Therefore, flow and structural ratings of inlets will, henceforth, be limited to those parameters visible and quantifiable at the surface. Measuring
Procedure. Only inlets constructed inL 􀁾􀀠within ten feet 􀁾rated pavement are rated. Rate all inlets in rated pavement. Include trench-type 􀁾􀀠well 􀁾􀀠box inlets. Flow 􀁾􀁾􀀠DISTRESS
NO. D4. Severity Levels. 􀁾Severity Level 􀁾􀀠Distress is limited to condition(sl . correctable 􀁾􀀠staff maintenance. such 􀁾􀀠debris in grates 􀁾􀀠catch basins. Low and medium severity
joint seal damage at perimeter of structure constitutes low severity inlet flow distress. Structural faulting 􀁾􀀠settlement of one quarter inch 􀁾􀀠less is 􀁾􀀠low severity distress.
Medium Severity Level 􀁾􀀠High severity perimeter joint seal damage constitutes medium severity distress. Structural faulting 􀁾􀀠settlement greater than one quarter inch but less than
􀁾inch is rated at medium severity. Sludqe at bottom 5 
Airport Pavement Inspection by PCI of catch basin less than one forth the depth of the smallest diameter connecting storm drain constitutes medium severity distress. (Mud 􀁾􀀠sludge
at 􀁾􀀠below flow line of the lowest outlet is 􀁾considered in rating inlets!. High Severity Level 􀁾􀀠Examples of high severity distress include. ill Sludge in bottom of catch basin
(not debris induced! deeper than 􀁾quarter of the depth of the smallest diameter connecting storm drain. 1£l Structural faulting or settlement of 􀁾inch or greater. Structural 􀁾􀀠DISTRESS
NO. D5. Severity Levels. Low Severity Level 􀁾􀀠Inlet and structure are generally serviceable. Distress is limited 􀁾􀀠condition(s! correctable Qy staff maintenance, such as tuck pointing
masonry and grouting small cracks in structure walls. Cracks in catch basin walls 􀁾􀀠floor 􀁾eighth inch wide 􀁾􀀠less with n£ faulting at cracks constitutes low severity distress.
Mortar damage in block walls is 􀁾􀀠low severity distress if blocks 􀁾securely in place. Medium Severity Level 􀁾􀀠Distress is correctable without major structural rehabilitation, such
􀁾􀀠􀁾􀀠broken inlet grate or cracked and faulted structure slabs. Cracked catch basin walls 􀁾􀀠floor less than 􀁾half inch wide with faulting less than 􀁾half inch constitutes medium
severity distress. Mortar damage in masonry walls resulting in voids between blocks, with 􀁾blocks loose but not broken 􀁾􀀠displaced is 􀁾􀀠medium severity distress. Any movement of
inlet casting under body weight of the inspector constitutes medium severity distress. High Severity Level 􀁾􀀠Correction of distress reguires major structural rehabilitation. Examples
of high severity distress include. ill Shattered structure slab with missing pieces and faulting of 􀁾inch 􀁾􀀠more, 1£l Shattered walls 􀁾􀀠floor of catch basins with mUltiple cracks
of one half inch or 􀁾and faulting at cracks of 􀁾half inch 􀁾􀀠more, L1l Missing pieces from walls 􀁾􀀠floor exposing reinforcing steel and mesh. 1!l Broken 􀁾􀀠displaced masonry blocks
in the structure. 6 
Errata 1. Page 2-16 Fourth Paragraph -First Sentence. Micro PAVER is now capable of generating curves to represent pavement deterioration. 2. Page 5-16 c. Area boundaries of Block Cracking
are defined by the outermost crack in the pattern. 3. Page 5-19 6. Cracks which define blocks larger than 2 feet on a side are not alligator cracks. Measure and record appropriately.
4. Page 5-20 Second Paragraph, (a) blocks which are approximately equally sided, and usually smaller than 6 inches on a side, (b) individual cracks usually rate at medium orhigh severity, 5. Page 5-47 Second Paragraph -First Sentence. The edges of a patch are considered as longitudinal I transverse cracks only while using Table 5-2 to determine patch severity;
these cracks are part of the patch and are not recorded separately as L & T cracks. Caption Beneath Figure 5-73, Edges of the patch are considered L & T cracks only while using Table
5-2 to determine patch severity; these cracks are part of the patch and are not recorded separately as L & T cracks. PAGE -1 
6. Page 5-63 The distress shown at Figure 5-88 represents an attempt at crack sealing. The distress is rated as an L & T crack. This is not a patch (does not replace original material).
7. Page 5-64 Third Paragraph -First Sentence. Any loose or missing pieces at a slab joint or corner are not considered in identification of distress types unless the resulting void is
at least 3 inches wide measured horizontally from the edge of the slab to the point where the void is 1/4 inch deep. Fifth Paragraph. Blowups, on the other hand, result from compressive
failure of either or both adjoining slabs through the full depth of pavement, or shattering (immediate displacement of pavement caused by explosive force) at the surface affecting more
than 50 percent of the joint length. 8. Page 5-66 Additional Criteria First Paragraph -First Sentence. By our interpretation of inspection criteria, a spall must be at least 3 inches
wide from the opposite face of the crack or from the edge of the slab. Second Paragraph -Second Sentence. A chip is a small piece of loose or missing concrete at crack or joint which
is less than 3 inches wide, measured horizontally from the opposite face of the crack or from the edge of the slab. Last Paragraph -Third Sentence. Little or no spalling or lightly spalled
means chipping defined by secondary cracks occurring over less than ten percent of the length of crack. PAGE -2 
\ 9. Page 5-76 Fourth Paragraph. The slab is divided into three pieces by low severity cracks. 10. Page 5-89 Additional Criteria Second Paragraph. Edges of the patch, are considered
L/T/D cracks only while using Table 5-3 to determine patch severity. These cracks are part of the patch and are not recorded separately as L/T/D cracks. PAGE -3 
APPENDIX A FEATURE DATA SUMMARY Instructions for use: Facility Description: Record the name most commonly used on the airport. (i.e. "Runway 12L-30R" or "Taxiway B" or "East Terminal
Apron"). Feature Location: Record pavement location within the Facility. (i.e. "From Taxiway C to end of runway" or "northeast 1/3 of taxiway" or "west side of GA apron"). MSL: This
is the Minimum Service Level for the Feature as designated by the Owner. (MSL is usually assigned by Facility, but may vary within a Facility if a significant functional change occurs).
Construction History: State year of construction and brief description (i.e."1982 2-1/2" flexible overlay" or,"8 in PCC on 12" cern trtd base on 6" soil cement subbase"). Present up
to four most recent construction projects in reverse chronological order. Do not record projects where the associated pavement has been replaced during more recent construction. Maintenance
History: Present types of maintenance performed, month and year of most recent application, and whether this was an initial application or part of a continuing program. Present brief
description of material/application (i.e. "rubberized bituminous· or ·Sand/Epoxy" or ·Chip Seal"). List materials used and brief description of specifications under "Additional Comments",
if information is available. Additional Comments: This section is for general use by researcher and inspector. Present any information which may be of value during inspection or evaluation.
Use reverse side of form, as necessary. 
____________________________________ ___ FEATURE 􀁾SUMMARY AIRPORT: ________________________________ FEATURE NO. _______ SURVEY YBAR: _____________ FACILITY DESCRIPTION: _____________________________
_________ FEATURE LOCATION: __________________________________________ FEATURE AREA: ______􀁾􀁓􀁑􀀮􀀠FT. MSL_____________ CONSTRUCTION HISTORY: (Maximum 100 characters per project).
A. _____________________________________________________ B. _____________________________________________________ C. _____________________________________________________ D. _________________________
____________________________ BASE COURSE: _________________ SUBBASE COURSE________________ UNDERDRAINS: _________________________________________________ SUBGRADE CLASS: _________________
MAINTENANCE HISTORY: Latest (month/yr) Previous (year) Type Crack/Joint Repair Patching Surface Treatment ADDITIONAL COMMENTS: 
' . I . .. 􀀺􀁾􀀠. . I 
\ \ I I i ,, APPENDIX B Sample Unit Data Sheets FLEXIBLE PAVEMENT Instructions for use: Heading information is self explanatory. Record number of measured feet, or square feet, of distress,
by severity. Multiple entries may be made for each in cases where complex measurements are required. Use care to make entries in the proper line. Transposed entries are sometimes difficult
to detect during quality review. Units will be totaled during quality review and at data entry. Make entries carefully and legibly. RIGID PAVEMENT Instructions for use: Heading information
is self explanatory. Sketch the slab configuration of the Sample Unit by connecting the appropriate dots on the form. Record each distress type and severity, by number/letter (i.e. "3L"
for low severity L/T/D crack, or "9" for pumping since there are not degrees of severity for pumping) in the space representing the slab in which the distress is located. Record jOint
seal damage in the "NOTES" area. DRAINAGE ENTRIES Record Pavement slopes to the nearest 0.1 percent. Record Shoulder slopes to the nearest 0.5 percent. Record Shoulder Condition and
Inlet ratings by severity. GENERAL COMMENTS Use a separate data sheet for each Sample Unit. Summarize distresses on each sheet at least daily. 
i I I .. FLEX.aLE PAVEMENT iT PAVEMENT CONDITION SURVEY SHEET 􀀭􀀧􀁜􀀢􀀧􀀧􀀧􀀺􀁴􀁾􀀧􀀠fEATURE 10 􀀵􀁁􀁾􀂷􀀢􀀧􀀻􀀧􀁅􀀠U"'11 f1iII\JMfH:01 fNUMll£R Of S::lUARl fEEt OAfE ISUAV£YU; 8't
􀁏􀁉􀁓􀀧􀀧􀀧􀁬􀁾􀁓􀀠TYPES SEvtR,fY LOil ME 0 " .....4 H'G" ft 􀁁􀁬􀀮􀁌􀁉􀁇􀁾􀁔􀁏􀁒􀀠CRAC"'NG 2 ILEEDING i 􀁾􀀠􀁉􀁉􀀮􀁏􀁃􀁾􀀠CRACkiNG • CORRUG,A TlON •􀁾OE""E SSION i II J£1 aLAST 7 JT
REFLECTION IPCC. 8 LONG" TRANS CRACkING 9 OIL SPILLAGE i 10, PATCHING In ft,)LIS'lED AGGREGATE !12 RAVELING'WEATHERING :R3 RUTTING II" " SHOVING fROM PCC 1'5 SLIPPAGE CRACKING 16 SWELL
NOTE: Measure'" Di.tr..... Sepototely Wh,pn Found In Co mbinotion W;,h ECKROSE/GREENOth., ... Diu,ess. Circle Combination. And Connt"ct wI lin•• ASSOCIATES 6409 ODANA ROAD MADISON. WISCONSIN
53719 608,274,6409 PAVEMENT SHOULDER SHOULDER INLET <:. liP!" S. \1'1= CON 􀁾􀁾􀀠, liFT RiGHT LEFT RIGHT LEFT liGHT FLOW rSTRUCT " 
• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • I . 􀀮􀁾􀀠,_.. M',... .--. ,
JOINTED RiGID PXVEMENT CONDITION SURVEY DATA SHEET fOR SAMPLE UNIT .. DATiAIAPORT 􀁾􀀧􀁁􀁃􀁉􀁌􀁉􀁔􀁙􀀠 IF£ATUIU 5"''''''''1.1 UNIT SI.AI SIZESURVEVED IV "􀁾􀀱􀁦􀀱􀁬􀀡􀁩􀀧􀀧􀀧􀀧􀀱􀀧􀁹􀁪􀁊􀀧􀀮􀀠PAVEMEN
T SHOULDER SHOULDER INLET 1 ....􀁾􀀠til ac.I.IH4....., CAACa/C".,INQ 􀁾􀁉􀁏􀁐􀁅1 QOfIUoI.......... SL PE CONDITION 􀁾􀁏􀁎􀁄􀁉􀁔􀁉􀁏􀁎􀀠U Mrn.......TI .. I...C)fIC;ITI,IO....U LEFT LErTRIGHT'nII_rv.I'
IMt '''''I.T RIGHT LEFT RIGHT IlATlNGSLOPE 􀁾􀁁􀁣􀀮􀀮􀀨􀀩􀁉􀁉􀁯..t. IJ 1H4fT•••O...."" ..... flOW II.. .11;)'''' sr.\. """".... ,." 􀁾􀀺􀁬􀁉􀀧􀀮􀁃􀀪􀀠it IHA,fo'U.GI Qo6....fol 1111,
"'..t.t.fIIH;__ ••rcIomc;..ca.r:l .10'"'''' , MTc..rM;1 tI ""'''1.'..0CIOI"...iIIIUTILIT"I' CUT STRver..,""'''"' 􀁾􀀧􀀧􀀧􀀧􀁬􀁉􀁏􀀠􀁎􀁑􀁾DIST, SIl". s ....... TV"! SKETCH 10 9 I I 8
7 NOTES 6 5 4 3 i 2._.><--! I ECKROSE /G REEN I • 6409 ODANA ROAD MADI!,ON WISCON!>IN 􀁾􀁊􀀷􀀱􀀹􀀠bIlH 27 4 6409 . 􀀧􀁾􀀠. "'q""" I 2 :1 4 5 6 _...... 􀁾
, j i 
I I \ BIOGRAPHY \ William H Green, P.E. Chief Engineer Eckrose/Green Associates, Inc. Madison, Wisconsin Bill Green is a professional engineer who has specialized in airport planning
and development for the past 16 years. He served as Airport Construction Engineer with the Wisconsin Division of Aeronautics. He was Chief Airport Development Engineer in the Iowa Aeronautics
Division. He served on the staff of the Des Moines Municipal Airport as Assistant Director. Before forming Eck rose/Green Associates with Roy Eckrose, he was Chief Airport Engineer with
a major engineer<ing firm in the Midwest. Since 1982, Bill has been developing and improving pavement testing and evaluation techniques for airports. He has been ProJect Manager of comprehensive
pavement studies at the Des Moines International Airport, El Paso International Airport, Tulsa International Airport, Fort Wayne Baer Field, and Hulman Field at Terre Haute, Indiana.
He directed inspection activities in a PCI runway inspection conducted at night, by by artificial lighting, at O'Hare Field; Chicago. He has organized and directed statewide airport
system pavement studies in Wisconsin and Indiana. He and Mr. Eckrose have developed an extensive library of computer software for evaluating and programming airport improvements. ProJects
currently in progress include statewide airport system pavement stUdies in Michigan and Minnesota. Mr. Green is an instrument rated commercial pilot with over 4000 hours in 25 years
of experience flying airplanes and helicopters. 
I \ BIOGRAPHY Roy Eckrose, P.E. President Eckrose/Green Associates, Inc. Madison, Wisconsin Roy Eckrose is a professional engineer who has nearly 30 years of experience in design, evaluation,
rehabilitation and recycling of pavements, including ten years as a consulting engineer preceded by more than 18 years in the Department of Public Works of a major Wisconsin city. Mr.
Eckrose has 􀁤􀁩􀁲􀁥􀁣􀁴􀁾􀁤􀀠inspection, testing and evaluation of pavement systems at the Des Moines International Airport, the El Paso International Airport, and the Fort Wayne and
Terre Haute airports in Indiana. He has directed special investigations of pavement at Tulsa International Airport and O'Hare Field, Chicago. He has managed pavement evaluation of statewide
airport system projects for States of Indiana and Wisconsin. He is presently managing pavement evaluation of statewide airport system projects for Michigan and Minnesota. Mr. Eckrose
is a respected public speaker on topics ranging from pavement to economics. He has published numerous articles on these and other subjects and has made presentations to various organizations
across the country. These include the American Concrete Institute, American Public Works Association, Federal Highway Administration, Wisconsin Aviation Conference and the National Asphalt
Pavement AssOCiation. He has taught and lectured widely at Universities of Ilinois, Missouri, and Wisconsin, and at Marquette and Iowa State Universities. Mr. Eckrose has written a comprehensive
library of microcomputer programs for pavement evaluation and management which is gaining national attention among airport owners and administrators as the most effective software available
for managing airport pavement systems. 
" : .; -, i