CF-Coppell Rd SC-CS020517CopPc11 °xryk~-CeNfer
May 17, 2002
Mark Murphy
Texas Unified Constructors, Inc.
803 E. Main Street, Suite B
Allen, Texas 75002-3100
Dear Mark,
~°~~
Z
~~`'z°°
~'~~ ~.
I want to let you know of concerns that the city has about the asphalt paving that was placed at
the pazking lot last week. First, the Engineering Inspector on the job asked that the paving not be
done on the morning of May 9 as there were items that he asked to be completed which were not.
In particular, the curbs were not backfilled, the densities of the subgrade had not been taken for
several weeks, there were areas of the subgrade that visually appeared to be failing and the
parking area had not been test-rolled to check for subgrade failures. Why was the subgrade not
test-rolled to check for failures?
Despite the warnings of the Engineering Inspector, the curbs were quickly backfilled and paving
was laid on a questionable subgrade. A small, patch roller was used to compress the asphalt into
place, the paving contractor opting not to utilize the large roller on site. Why was the lazge roller
not utilized? You know that the soils in the area of this project are very expansive. This is one
reason the lime stabilization was specified. It appeazs that by placing the asphalt over this
questionable subgrade, the effectiveness of the stabilization could be minimized.
I am not sure what the rush was to get this paving completed, other than the continued
deterioration of the stabilization. It just seems that, for TUCI's protection, some checks would
have been completed to certify that the subgrade was still structurally sound. There are
significant areas where the paving needs to be removed and the subgrade reworked and I suspect
that there are failures other than those that are visible on the surface.
Please explain why this paving was pushed to completion last week and outline for me TUCI's
plan for ensuring that the subgrade is sound, the asphalt meets standazd specifications and the
plan for removal and replacement of the asphalt and subgrade. I expect that densities will be
taken of the existing pavement and subgrade to determine where azeas do not meet specifications.
Because the subgrade was so inconsistent from one area to another, there should be densities
taken in a variety of locations to make this assurance. There should be no top-coat layer placed
on any asphalt until the subgrade and base course are accepted by the city.
Sincerely,
Brad Reid