Freeport NIP(1)-CS 970514l~l' 8616 NORTHWEST PLAZA DRIVE
Halff As i ate
S O C S
ENGINEERS · ARCHI~CTS · SCIENTISTS
PLANNERS - SURVEYORS
May 14, 1997
AVO 16192
Mr. Kenneth Griff'm
c/o Michael Mart~
City of Coppell
255 Parkway Boulevard
P.O. Box 478
Coppell, Texas 75019-4409
Dear Mr. Griffin,
Halff Associates, Inc. would like to submit an alternative pavement design for
Freeport North Distribution Center. For the parking area, the alternative design is 5 inch
thick 4000 PSI compressive strength concrete with//3 bars, 18 inch O.C.E.W. on
compacted subgrade in lieu of the 5 inch thick 3000 PSI compressive strength concrete
with #3 bars, 24 inch O.C.E.W. on 6 inch lime stabilized subgrade as shown in Appendix
C of the City of Coppell Subdivision Ordinance. For the truck courts and fare lane, the
alternative design is 6 inch thick 4000 PSI compressive strength concrete with #3 bars, 18
inch O.C.E.W. on compacted subgrade in lieu of the 6 inch thick 3000 PSI compressive
strength concrete with #3 bars, 24 inch O.C.E.W. on 6 inch lime stabilized subgrade
shown in Appendix C of the City of Coppell Subdivision Ordinance.
I have included a section of the soils report for your reference. If you have any
questions or require any additional information, please contact Pat Acker or myself.
Sincerely,
HALFF ASSOCIATES, INC.
Todd Abbott
cc: David Meinhardt
Rob Ahmuty
Mark Jacobson
DALLAS · FORT WORTH · HOUSTON · McALLEN
TRANSPORTATION · WATER RESOURCES · LAND DEVELOPMENT · MUNICIPAL · ENVIRONMENTAL. STRUCTURAL
MECHANICAL · ELECTRICAL · SURVEYING · GEOGRAPHIC INFORMATION SYSTEMS
ARCHITECTURE · LANDSCAPE ARCHITECTURE ° PLANNING
05×13x97 15:59 MEINHARDT AND QUINTANA - 214 ?39 0095 N0.997 Q02
Thc spccific p~vcment section will be dependem upon'
I. traffic loads and J?equency;
2. pavement type and slrcngth:
3. desired pavement life and ending condition: and
4 strength and condition of the subgradc
Information regarding the specific lratt~c loads and fi'cquency is not available. Therefore,
analysis was pcrl~'ffmcd 1~- a n~nge of InsilCo conditions, ami design} thickness versus lraI]~c load
diagrams were developed.
The pavcmcnl type has been identified as c(mcrcle Analysis was pcrlbrmcd t3r bolh 3,000
pounds per square inch {psi) and 4.000 psi compressive strength concrele. Based on
correlations between compressive strength and llc~m'al slrcng~h, m~d incorporating a t~ctor of
safety o1' 1.33, an allowable working stress of 370 and 425 psi was used for thc 3,000- and
4,000-psi concrete, respectively. Control of the water cement ratio at thc design value during
placemenl ~md usc of quality coaslruction will be necessary to achieve the required llcxural
strength
A 20-year life was used fbr thc analysis Total pa,'cmcnr life wits based on a si__Ex-day week.
Analysis was performed in accordance wi~h i)roceclm'cs dc~.'clopcd hy the American Association
of State Highway Officials (AASI I0)[Yoder. 1~)75]
Report No. 2959 10 - Junc 30. 1996
The upper surt~ce soils consist of CH cl~ys. When these soils arc moist, they are relatively soft.
For purposes of pavement analysis. ~he subgradc was assumed to t,e rccompacted in accordance
with the density and moisture recommendations in thc E~u'lhwt~rk scclion and itl a moist
condition. An effective modulus of subgrade re~tctirm, k. ot' 100 pci was used fbi' the analysis.
Thc effective k val6~ ~1' the subgrade can bc h~crcascd to 270 pci by stabilization of the upper 6
percent hydrated shtmld be placed and compacted in
il~ches
o~'
lime.
accordance with I~em 26~ of the current edition of TxDOT "St~mdard Specificaticms
Const~'uction of l lighways, St~'ect and Bridges" The lim~ stabilized subgrade should be
compacted ~o a minimum of 100 pcrccm of ASTM D-698 density (Standard Proc/or) unless
otherwise specified
Generally. it is more cost-cll~ctivc [o increase ~hc pavement thick,,ess and construct over a non-
lime stabilized sub?'adc S~abilization does however provide an all-weather' ~,orking platlbrm
for the conlractor, and II, is may be beneticial f?om a
also generally recommended if ~he traffic speed exceeds 30 miles per hour (mph).
Considering thc abovv discussitm, aI~al)'sis was made fi~r both unlimited repetitions of cars and
lighlIrucks~nd fi.~'mtd~iplerepetititmsofloaded t~'actor trailers Analvsisindicatesa pavement
thickness ~1'4 5 inches of 3.000-psi concrete will be adequate
Ininimttm fivc-incl~ sec[ion is recommended
Report No 2'.')59 - I I - Junc 30, 1996
05x15×97 15:58 MEINHARDT AND QUINTANA ~ 214 959 0095 N0.999 Q04
Pavcmcnts subject to i'nuldple repetitions of tractor trailer tralfic wcrc analyzed Using both
3,(JO0- and 4,000-psi c(mcrulc. Trailers were assumed to be loaded to thc maximum allowabl~
wcighL 80 kips. consisting ot'tw(~ sets of ~andem axles loaded to 32 kips, and one 16-kip axle.
l~ecommcndcd sec~i(ms fbr vari()us fi-equcncy of truck ti'attic, bascd on number of repetitions
per day for a six-da~ week. are provided h~ the Rfllowing tables.
il TABLE 1 (K=I'00
PCI)
NUMBER OF TRUCK REPETITIONS VS. PAVEMENT THICKNESS
3,000-PSI COMPRESSIVE STRENGTH
':~
Pavement Thickness No. of Repetitions
(inches) (per day)
6 9
~ 7 22
8 52
I 9 t10
TABLE 2 PCI)
(K=100
NUMBER OF TRUCK REPETITIONS VS, PAVEMENT THICKNESS
4,000-PSI COMPRESSIVE STRENGTH
-I
Pavernent Thickness No of Repetitions
(inches) (per day)
6 13
7 33
8 82
9 163
Report No. 2959 - 12 - June 30, ! 996
05/13/97 15: 58 I"IE ! NH~RDT I:qND O.U 1NT~NFt .-, 2 J. 4 ,.?3c:j 0095 NO. gg? 1~05
Am, lysis of' Tablcs 1 and 2 indicates an approximate SO To ~0 percent incre~s~ in the number o£
truck repetitions c~n be obtained by increasing Ihe concrete .~trength Ikm~ ].000 psi to 4,000 psi.
An increase oF 100 t~ I SO percen~ is realized by increasing d~e d~ickness ot'd~e pavemen~ by one
inch.
Although not pro,.'idcd herein, analysis of' ~1~¢ allowable repetitions was also performed
considerin~ a s~abilized 5ub~radc For any given pavemcat thickness and strcn~lh oficoncrct¢,
an increase in fl~c numbcr of rcpc~itions cqual to 20 to 33 pcrccm of ~he non-stabilizcd
rcpc[itio~s i~ r~alizcd ('ousidcrmg ibc ~cla[ive cos[s ~ssocia~cd wi~h s~abillzin~ ~hc subgrade.
~rcater increase in r~petition~ (i.e.. pavement li17) is realized by inc~'easin~ the pavement
thickness or strength versus stabiliz~ttion of the sub~radc.
Pavemcnts should bc li~htl), r~inlbrced il' slu-inka~c crack control is dcsircd. ILeinForcin~ tbr
and G-inch pavements shot,Id consis~ ~fthe equivalenl ol'f13 bars a~ I~ inches on-center.
Pavement sections should be saw cut at ~n ~pproxima~e spacin~ in fo¢~ of 2.5 times
pavemen[ [hickncss cxp,'cssed in inches (For example, a 5-inch pavement should be saw cut in
approximate 12 5-thor squaFcs.) Thc actual joim pauern shuuld be carefi~lly dcsigncd to avoid
ir,'e~ular shapes Rccommended~oimin~ teclmiques ~rc discussed in de~ait in "Joint Design For
C'o~crctc Iliuhwav,. . aud St,cot Pavcmcms". publish¢d h¥ iht ?ortl~ad Q~cm~nt ,.~'~-t~c~at*,~--'-'i-nlinC'Au . -' '
Report No. 2959 13 - June 30, 1996
05/15/97 15:58 MEINHARDT AND QUINTANA -~ 214 ?59 0095 N0.997 Q06
ConstruclJon Obse~'vation
It is recommended that a reprcscn[alive o1' I~is olllce be present during construction of
foundations in ordcr IO conlh'm a proper bearing Sil'attllll and ct)nslructJOn procedures.
Field density tests should be l)e'R)rmed by a r~l)cesentative ol'this ull~ce at a minimum tale
one tes~ per 5,000 s?are fe~t per lift in d~c building areas. The compacicd moisiure and density
of.utility trench backfill sh()uld bc testud al a minimum rate oF onc l~st per 200 linear feet of
trench, per liit. Area~ t() receive paving should be tested at a ra[c oJ'onc tesl per I0,000 square
thcl per lift.
Full time observation of thc water opcra~ions by
in
this
o~ce
is
recommended. Post-injection borings
Sl)ecific;~ions scctio~
I{EFERENCE$
"~ed~od for Determining [l~c Potential Vertical Rise, PVR" (1978). Texas Dep~ment
of 'l'ranspor~ation, Tes~ Melhod Tcx- 124-E.
Yodcr~ l~J. and Witczak, M.W. (1975)~ "Principles
Sons, lac.. New York. N Y.
"Joint Design fi,r Co~crete Highway a~cl Street Pavements" (1980). Portland Cemcn(
Association. Skokie,
Repot! No. 2959 - 14 - June 30, 1996