SC-Wilson E5-CS 910308 '- ' I RIIl 911 !,
March8, 1991 j i\[ HAR I 2_ 1991 .
Mr. SteveGoram ................... "~' .... '~":"" '._.~~/'"~~~
Dire~or of Public Works - ~ n)~ [0
City of Coppel, ~. ~
732 Deforest r~ , ~,'
coppell, Texas 75019
On ~ohalf of Goppoll 1.8.D., 8HW~, In~. mquo~t~ a hoarin~ o[ tho Goppo Gi y ' n
varianeo for tho a~ovo montionod
Goppoll 1.8.~. wou~d Iiko to roquo~t a chan~o from tho pm~ont roquimmonts o~ ~' thick con-
croto pavin~ to 5" thiok concrot~ pavin~ in tho parkin~ and light tragic aroas. ~ll bus and
ico drivos will bo constructod with ~ thick coneroto pavin~. ~11 eoncmto pavin~, whothor 5" or
~", will Bo insIallod on limo staBilizod sub
This roqu~st is ~in~ mado ba~od on th~ in[ormation providod ~y M~im fin~ino~m, whoso soil
invosti~ation indicato~ that a 4" thiok oonoroto pavomont ~o~ion for tho parkin~ and light tragic
areas is sufficient for these sele~ed areas. I have included the se~ion of this soils repo~ per-
taining to pavement recommendations for your review.
Coppell I.S.D. applied for and was granted this ve~ same request for the parking areas at Cop-
pell High School parking areas, Austin Elementa~ 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 maEer.
Sincerely,
SHWC, Inc.
Michael L. Elmore
Senior Associate
ME/kc
Enclosures
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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. --
9. 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 gr~bbed 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):
13
Areas of Light Vehicular Traffic
5.0 inches Portland Cement Concrete
(12 feet Joint Spacing)*
6.0 inches Compacted Lime Stabilized
Subgrade~*
Areas of Channelized Vehioular Traffic
6.0 inches Portland Cement Concrete (12 feet Joint Spacing)*
6.0 inches Compacted Lime Stabilized
Subgrade**
*See guidelines for concrete parking areas in the
Appendix of this report.
**With the addition of four (4) percent of hydrated
lime by unit dry weight of soil.
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 500 vehicles per
day including five (5) to seven (7) heavy commercial
trucks. The pavement section should be redesigned if
traffic loading, volume and other conditions exist
outside those previously mentioned.
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