John:

 

I have not been able to review your pavement design this weekend. I hope to have our comments to you by noon on Monday.

 

Frank McIllwain, PE
Garver

 

From: John Johnston [mailto:jwjohnston-hja@sbcglobal.net] 
Sent: Friday, May 21, 2010 11:31 AM
To: McIllwain, Frank O.
Subject: ExecHangar Pavement

 

Frank -

 

Attached are FAARFIELD analyses intended to represent the minimum
value anticipated from the available pulverized material at the site
utilized as base.  That material is represented as having a CBR of 20
and E determined as 1500 x CBR.  A CBR test will be performed on the
material to determine its actual CBR level. Grain size distribution also 

will be determined. The analysis sheets for base thicknesses from 6
inches to 18 inches are attached.  

Assuming the CBR test gives us a value of 20 or above I will define 

the final design criteria to allow the owner to proceed.

Based on the proposed CBR testing the owner intends to pull up the
existing aggregate base and stock pile it on the site. They will also
remove and separate the existing clay soil and dispose of it off site, thereby 
eliminating all expansive soil material down to the weathered limestone. They will then place the existing aggregate base in engineered lifts and the concrete paving
per final recommendations.

The owner would appreciate your approval of the above procedures, so
that he can move forward. Could you please let me know your thoughts
at your earliest convenience.

 

Thanks,

 

John

John W. Johnston, P.E.

Henley-Johnston & Associates, Inc.
235 Morgan Avenue
Dallas, Texas 75203-1025
Texas Firm Registration No. F-1238
Phone: 214-941-3808
Fax: 214-943-7645
e-mail: jwjohnston-hja@sbcglobal.net