Cambridge Phase 1-CS 940901r G
EOTECHNICAL
NGINEERING I~t
EE [NVIRONMENTAL GEE Consu s, Inc.
2540 Glenda Lane · Suite 108 · Dallas, Texas 75229 · (214) 620-9791 · Fax (214) 620-9794
September 1, 1994
Mr. Jack Bommarito
Beamer Development Company
P.O. Box 2312
Coppell, Texas 75019
RE: Estates of Cambridge Manor, Phase I
Coppell, Texas
Dear Mr. Bommarito:
At the request of Mr. David Carlton of Dowdy, Anderson and Associates of August 30,
1994, a representative of our firm visited the above referenced site. The requested purpose
of our site visit was to sample and evaluate the upper six (6) inches of exposed pavement
material on Deforest Road. It was our understanding that the surface asphaltic concrete of
a portion of Deforest Road adjacent to the above referenced project had been pulverized and
mixed into the underlying base material and the pavement used as a haul road.
As per our discussion with Mr. Carlton, you wish to determine the feasibility of utilizing
existing pavement base material, pulverized asphaltic concrete and some haul spillage already
in-place. Requested recommendations are for a pavement section generally equivalent to six
(6) inches of base material and two (2) inches of asphaltic concrete.
Betuner Development Compm~y September 6. 1994
Three (3) samples from Deforest Road were taken August 31, 1994. The purpose for
sampling was to perform gradation and plasticity index testing of exposed pavement
materials. Test results are as follows:
NCTCOG Flexible Base
Gradation Test Results Requirements
Plasticity
Index Test Percent
Percent Results Passing Plasticity
Sample Location Sieve Size Passing Percent Sieve Index
Deforest Road I SA" 100.0 100
210' west of
Allen Road, No. 4 62.3 35 to 55
Centerline No. 40 16.0 13 15 to 40 4 to 12
1 sA" 100.0 100
Deforest Road at
Allen Road, No. 4 81.0 35 to 55
Centerline
No. 40 40.0 19 15 to 40 4 to 12
Deforest Road I sA" 100.0 100
300' east of
Allen Road, No. 4 66.8 35 to 55
Centerline
No. 40 48.3 16 15 to 40 4 to 12
Based on the above test results and our experience, we recommend the following pavement
section be considered as generally equivalent to six (6) inches of base material and two (2)
inches of asphaltic concrete:
6" Existing Base Material
3" New Flexible Base Material
2" Type "D" Hot Mix Asphaltic Concrete
The existing exposed surface should be scarified and re-compacted to between 95 and 105
percent of the maximum dry density as determined by ASTM D 698 (Standard Proctor Test)
at a moisture content within plus or minus three (3) percent of the optimum moisture value.
New base material should then be placed and compacted to between 95 and 105 percent of
the maximum dry density as determined by ASTM D 698 (Standard Proctor Test) at a
moisture content within plus or minus three (3) percent of the optimum moisture value. New
flexible base should meet the requirements of NCTCOG Standard Specifications.
GEE Consul 'tants. inc. Page 2
Be,-uner Development Company September 6, 1994
Hot mixed Type "D" Hot Mixed Asphaltic Concrete should meet the requirement of Texas
Highway Department Standard Specification Item 340.
We trust the above information meets your needs. If you have any questions or if we may
be of further service, please do not hesitate to contact us.
Sincerely,
GEE Consultants, Inc.
Gary G. Huang, Ph.D.
Geotechnical Engineering Division '
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Enclosure(s) :~ c,. e ~ ,. ~, .~.
cc: Mr. Bill Anderson - Dowdy, Anderson and Associates
Mr. Ken Griffin - City of Coppell
GEE Consultants. lac. Page 3