Tax 2011C-CN110629 ALLIANCE
GEOTECHNICAL • GEOTECHNICAL ENGINEERING
GROUP • ENVIRONMENTAL CONSULTING
• CONSTRUCTION MATERIALS ENGINEERING AND TESTING
June 14, 2011
Mr. George Marshall, P.E.
City of Coppell
255 Parkway Blvd.
Coppell, Texas 75019
Phone: (972) 304 -3562
Email: gmarshall(a)coppelltx.gov
Re: Proposal for Pavement Distress Investigation
Sandy Lake Road
Coppell, Texas
AGG Proposal P11 -0606E
Dear Mr. Marshall:
Alliance Geotechnical Group understands that we have been selected to provide pavement
distress investigation services for the above referenced project based upon our qualifications in
accordance with the Professional Services Procurement Act. Hence, AGG is pleased to submit
this proposal for pavement distress investigation services for the project site referenced above.
This proposal includes a description of the project, scope of work, and estimated fee.
PROJECT DESCRIPTION
The project consists of Sandy Lake Road between Denton Tap Road and MacArthur Blvd. in
Coppell, Texas. We understand that areas along this roadway are experiencing some
pavement distress and some failure. We understand that about 10 years ago that Sandy Lake
Road was reconstructed from a 2 lane undivided asphalt pavement to a 4 lane divided concrete
pavement. We further understand that the new pavement section was specified to consist of 8
inches or reinforced concrete pavement (3,000 psi) over 8 inches of Time- stabilized subgrade.
SCOPE OF WORK.,
The pavement distress investigation performed for the referenced project will consist of field
and laboratory investigations, engineering analysis, and a report prepared by a Registered
Professional Engineer.
Field Investigations
The field investigation for the pavement distress investigation will consist of drilling ten (10) sets
of test borings in existing distressed areas. Each set of borings will consist of drilling one (1)
test boring using continuously Standard Penetration Testing (SPT) techniques in conjunction
with split spoon sampling within existing utility trench backfill to determine the relative density of
the backfill and drilling one (1) test boring using continuous Shelby tube sampling techniques
outside of the utility trench backfill. The Shelby tube test borings will be drilled to depths of 10
MEMBER 3228 Halifax Street • Dallas, Texas 75247
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1 GROW City of Coppell
Pavement Distress Investigation
Sandy Lake Road
AGG Proposal P11 -0606E
June 14, 2011
Page 2
feet below top of pavement. The SPT test borings will be terminated at depths above the
existing utility lines in order to prevent damaging the lines. Depths of the subject utility lines will
need to be provided by the City.
In addition to the test borings drilled within the existing distressed areas, three (3) control test
borings will be drilled in areas that do not show signs of distress. These borings will be drilled to
depths of 10 feet using Shelby tube sampling techniques. A total of twenty three (23) test
borings will be drilled for this distress investigation.
At each boring location for the distress investigation, the concrete pavement will be cored using
a coring machine and a 4 to 6 inch diameter core barrel. The thickness of the cores will be
accurately measured along with the thickness of any void beneath the pavement at the core
locations and the thickness of the lime stabilization.
All samples will be properly logged, packaged, sealed, and placed in a core box for
transportation to the laboratory. The test borings will be backfilled and the pavement patched
upon drilling completion.
This proposal assumes right of entry will be obtained by the City to allow access of our drilling
rigs to the boring locations. We understand that traffic control will consist an "Arrow Board ",
channeling devices and signs only. Extensive traffic control (including flagmen) have not been
included in this proposal. For safety purposes, the drilling will be performed with drilling rig
facing into traffic. Should unusual soil conditions be encountered, we will call you with a
recommendation and cost estimate to explore these unusual conditions.
Alliance Geotechnical Group will contact Dig Tess and the City of Coppell to have them locate
underground utilities. Alliance Geotechnical Group will also meet with the utility locators in the
field to identify the boring locations. However, Alliance Geotechnical Group is not responsible
for damage to underground utilities that are not identified prior to drilling.
Laboratory Investigation
Laboratory tests will be conducted to classify the soil and to evaluate the volume change
potential and strength of the soil present at the site. Moisture content tests, Atterberg limits
tests, percent passing #200 sieve tests and sulfate testing will be performed. The strength of
the soil will be estimated using hand penetrometer test and unconfined compressive strength
testing. The volume change potential of the soils will be evaluated by swell tests.
Compression testing will be performed on half of the concrete cores. In addition, Atterberg limits
testing will be performed on half of the lime- stabilized samples recovered beneath the existing
pavement.
ALLIANCE
GEOTECHNICAL
GROUP City of Coppell
Pavement Distress Investigation
Sandy Lake Road
AGG Proposal P11 -0606E
June 14, 2011
Page 3
Engineering Analyses
Results of field and laboratory work will be presented in an engineering report. The report will
include the following:
1. Site reconnaissance and staking by Alliance Geotechnical Group Engineer.
2. Plan of borings, boring Togs, water level observations, and laboratory test results.
3. Thickness of pavements, thickness of voids, and depths of lime- stabilization.
4. Potential Vertical Rise (PVR) calculations at each boring locations.
5. Determine the probable causes of the current pavement distress.
6. Determine the potential for additional distresses.
7. Recommendations for remedial work.
GEOTECHNICAL FEES AND PROJECT SCHEDULE
Based on the proposed scope of work, we will provide the geotechnical investigation for this
project for a lump sum fee of $24,950.00.
TERMS AND CONDITIONS
If this proposal meets with your approval, please sign below to authorize Alliance Geotechnical
Group to perform the work.
We look forward to working with you on this project. Please contact us after reviewing our
proposal if you have any questions.
Sincerely,
ALLIANCE GEOTECHNICAL GROUP •.
Michael D. olan , P.E.
Principal
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