SC-Wilson E5-CS 910308March 8, 1991
Mr. Steve Goram
Director of Public Works
City of Coppell
732 Deforest
Coppell, Texas 75019
DearRE: Mr.C°ppellGoram:Elementary School #5
On behalf of Coppell I.S.D., SHWC, Inc. requests a hearing of the Coppell City Council on
variance for the above mentioned project.
Coppell I.S.D. would like to request a change from the present requirements of 5" thick con-
crete paving to 5" thick concrete paving in the parking and light traffic areas. All bus and serv-
ice drives will be constructed with 6" thick concrete paving. All concrete paving, whether 5" or
6", will be installed on lime stabilized sub base.
This request is being made based on the information provided by Maxim Engineers, whose soil
investigation indicates that a 4" thick concrete pavement section for the parking and light traffic
areas is sufficient for these selected areas. I have included the section of this soils report per-
taining to pavement recommendations for your review.
Coppell I.S.D. applied for and was granted this very same request for the parking areas at Cop-
pell High School parking areas, Austin Elementary School and Mockingbird Elementary School.
I would appreciate your consideration of this request and would like to be considered for the
earliest possible date for the City Council's upcoming meeting,
Should you need any additional information please do not hesitate to call me. My telephone
number is 550-0700. Thank you for your assistance in this matter.
Sincerely,
SHWC, Inc.
Michael L. Elmore
Senior Associate
ME/kc
Enclosures
12
ensure that undesirable fill that was not detected
by the test borings, does not exist at the site.
This office should be notified immediately if any
such fill is detected.
At Grade Pavement Recommendations (Surface and Drives)
Prior to beginning pavement construction, soils at the
natural ground surface in the proposed drive area
should be scarified and grubbed to a depth of at least
six (6) inches.
Organic materials and any vegetation should be removed
from the site. The scarified areas, along with areas
requiring additional fill, should then be recompacted
to a minimum of 95% of Standard Proctor Density as
defined by ASTM D 698 at a moisture content between
optimum and five (5) percent above the optimum moisture
value.
The following pavement sections are a minimum recom-
mended for the soil conditions existing on the site
(15-year life design):
MAXIM
13
inches
inches
Areas of LiGht Vehicular Traffic
5.0 Portland Cement Concrete
(12 feet Joint Spacing)*
6.0 Compacted Lime Stabilized
Subgrade~*
6.0 inches
6.0 inches
*See guidelines
Appendix of this report.
**With the addition of four (4)
lime by unit dry weight of soil.
Areas of Channelized Vehicular Traffic
Portland Cement Concrete
(12 feet Joint Spacing)*
Compacted Lime Stabilized
Subgrade**
for concrete parking areas
percent of
in the
hydrated
The light duty pavement is designed for 200 to 300
vehicles per day, two (2) to three (3) of which may be
heavy commercial trucks. The channelized traffic
pavement is designed to sustain 300 to
day including five (5) to seven (7)
trucks. The pavement section should
traffic loading, volume and other
outside those previously mentioned.
500 vehicles per
heavy commercial
be redesigned if
conditions exist
MAXIM