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Freeport NIP(5.2)-CS 970514'"',,, Halff Associates 19-97 ~*i~: ~..~ae,6. NORT.WEST PC^Z^ OR,V[.: ' D^LL^$.21TEXAS4) 739-009475225 III F^x 214)73§-0095 ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS · SURVEYORS May 14, 1997 .... AVO 16192 ........... Mr. Ke~e~ ~ffin ~ ~ c/o Michael M~in J - . r~'a Ci~ of Coppell ? :"~ .... . 255 P~kway Boulev~d P.O. Box 478 Coppell, Tex~ 75019-4409 / De~ 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 fire 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 05xlSXg? 15:57 MEINHARDT AND DUINTANA -. ~14 ?59 0095 N0.997 DO~' Thc spccilic p~vcmen( ~cc[i(~[~ will be dRpendofll Lq)on' I_ traffic Io~d~ and I~equency. 2. pavement type and 3. desired pavement life, and ending condition: and strength and cemdition ofthe subgrade Information regarding ~l~e specific tratt~c loads and fi'cquency is not available, lherefore, analysis xYas pcrl}'~r~ucd lbra n~ng~ oF Iral]~c condit ohs and dcsigu tldckness vcrsus u'al]~c load diagrams were dcvelooed. The pavcmcn~ type has b~en id~nlifi~d as c~mcrc~ Anah'sis was p{)unds per square inch (psi) and 4,000 psi cc)ml)~-essivc SlrCilglh concl'~i~ Based on correlations betwee~a compresswe s!~'ength and l]cxural slreng~h, and incorporating a t~ClOF of safety o1' 1.33. an allowable working stress of 370 and 425 psi was used for the 3,000. and 4,000-psi concrele, respectively Cm~trol of'the water cement ralio at Iht design value during placement and use of qua!it), conslructinn will be nccessm'y to achiex, e the required flexural strength A 20-)'~ar lltb was used fbr lhe anal)-sis Total pa,.cmen~ life was based on a six-day week. Analysis was pcrl~rmed in accorclance x,i~h ps'oceclurcs developed hv thc American Association of State Highway Ot~icials (AASI I0)[ Yodel 1975] Rep~.~r! No 2959 - I0 - Jr. nc 30. 1996 15:59 MEINHRRDT AND OUINT~NR ~ 214 ?~9 Tile upper surJ'ace soils consist oFCH clays When these soils arc moist, they are relatively soft. For purposes of pavement analysis. ~he sul)~ra(l¢ was a.csumed to be rccompacted in accordance wilh thc density and moisture rccommend:mons in ll~e Earlhworl< g¢clion and in a illOi$1 condition J~J'J efl'~ctive modulus of subgrade reaction, k. oF 100 pci was used Ibr thc analysis. l'hc cflkctivc k valfk: of thc subgracle can bc incccascd to 27o i)ci by s~abilization of the tH)per 6 inches wi~h a minimum of six l)C,'CCnt hydrated lime i.ime sht)Llld be placed and COml)aclcd in accordance with llem 260 of the current etiitff)n of TxDOT "Standard Specifications Construction of [ligh,~'ays. Street and [3m'i(Igcs" 'l'i~e Ihnu stabilized subgrade should be compacted Io a mininlunl of 100 pm'cen~ of ASTM D-698 density (Standard Proctor) unless otherwise specified (.Jcrlcra!iy. iL iS l~lO;C COSt-cl]'~Ctiv¢ tO increase Ibc pavenlent :hick;'.css and construct over a non- lime stabilized stmbgrade S:abilization does h{~wcvcr provide an all-weather ~.orking platlbrm for the contractor, and this may be beneficial I?om a consmmction perspective Stabilization is also generally rccommcndcd if ~hc traffic si)ccd exceeds 30 ,idles pc~-hour (mi}h). Considering the above d~scussiLm, analysis ,,'as made for both unlimited repetitions of cars and light [rtmckx and c,o,.- m~ltiple, rcpcutions c)f loadcd tractor trai]ers Analysis indicates apavcmcn[ thickness t)l'4 5 inches of .i.00O-j)5i concrete ~ ~l be adeClUatC for car and I~ght truck Iraflic. A minimum five-inch section is recommended Report No 2959 - II - Junc30, 1996 05/13/99 15:58 MEINHARDT AND QU]NTANA ~ 214 939 0095 N0.997 ~04 Pavcmcnl:s subject to multiple repethions of tractor trailer I. rafl~c wore analyzed usin~ both 3.000- and 4,000-psi conc,'cle. Trailcrs wcrc assumed ~o be loaded to thc maxin~un~ allowabl~ wcighL 80 kips. consisting of tw() sets of tandem axles loaded to 32 kips, and one 16-kip axle. Recommended sec~i(ms I%r various fi-equcncy o1' truck ~rattic. based on number off repetitions per day for a six-d~~ week. are pcovided in ~l~e fi~llowing ~ablcs. TABLE I (K=100 PCI) NUMBER OF TRUCK REPETITIONS VS. PAVEMENT THICKNESS ..Il~ 3,000-PSI COMPRESSIVE STRENGTH Pavement Thickness ........ No'. Of Repeti!ion~  (roches) (per day) 6 9 ~ 7 22 8 52 '~ 9 110 Ill TABLE 2 (K=100 PCI) NUMBER OF TRUCK REPETITIONS VS. PAVEMENT THICKNESS 4,000-PSI COMPRESSIVE STRENGTH Pavement Thickness No of Repetitions (roches} i (per day) 6 ~3 7 33 9 163 Report No. 2959 - 12 - June 30, 1996 05xlSx97 15:58 MEINHARDT AND QUINTANA -~ 214 ?39 0095 NO. 999 Q05 Analysis of Tables I and 2 indicates an approximate 50 [o 8o percenl increase in the number of truck repetil OhS can be oNained by incre~sin~ Ihe concrde strength ffo~n 3.000 psi to 4.000 psi. An increase of 100 t~ I ~0 percent is rc~dizcd by increasin~ ~l~e d~ickness of tl~e p~vcmen~ by one inch Although not pr~'idcd herein, analysis of tl~c allowable repetitions was also performed considering a slabilizcd sub~rade For any riven pavement thickness ~nd strcngd~ of concrete. an increase in [l~c number o/' rcl)clhtons equal to 20 t(~ 33 l)CrCCm of the non-stabilized rCpClitiO~LS is realized ('o[~sidcrm~ thc [clative COS[S associated with stabii[zmS Thc subgrade, a greater increase in repetitions (i.e.. i~a,'emcnL lil~) is realized by increasing Lhe pavement dtickness or strength versus stabilization of the subgradc. Pavements should bc li~41~t[y rcinlbrced ~['shrinkagc crack control is dcsi~'cd Iieinforcing lbr 5- and 6-tach pavements should c~msist ~fthe equivalent of it3 bars a~ l g inch¢~ on-center. Pavement sections sht~uld be saw cu~ at an approximale Sl~aCing in fcc~ of 2.5 times pavement [hickncsscxprcsscd in inches (Forexampl~.a 5-inchpavement should bcsaw cut approximate 12 5-Ibot ~qUal'CS.) Thc actual joint panern ~hould bc carcfhlly dcsigncd to avoid irrc?lar shapes Recommended jomling techniques arc discussed in deta~J ht "Joint Design for C'oncrctc l ligl,wav ~tJ S~cct Pavcmcms". i)t~blisi~cd hv llic Po~tla:~d Cemen~ ..X:~:~ociation[I~('A. i i Report No. 29.':,t) 13 - JuB¢ 30. 1996 ~/iJ;/~? 15;58 MEINHARDT AND ~-'UINTANA - 214 ?59 0095 N0,997 Q06 Constru¢lion Obse~'valion It is recommended that a representative o1' this ollice be pccsent dut'ing construction of the foundations in order Io corilh'm a proper bearing stratum and construclion procedures. Field density tests should be peril)treed by a rel)cesentative of this ullice at a minimum rate of one test pec 5,000 square feet pc~' lift in thc building a~'eas. The compacted moisture and density of utilily trench backfill should be tested a~ ~ minimtm~ rate of one lest per 200 linear feet of trench, per h,t. A~'cas t() receive pavin~ sh(~uld be tested at a rate el'one test per 10,000 square t~et per :" Full time observation of the water Jn.j¢clion op¢ca~it:ns by a ~'cl)resenlative o~ this o~ce is recommended. Post-injection bt~'in~ should he l)crii~'med in ~cco~'dance with the Specifical ions scction I{EFEI{EN(:ES "Method flor Detcn~ining tl~e Potenlial Vertical Ris~, PVR" (1978). Texas Depa~ment off Transpor'~a~ion. Test b4elh(~d Tex- 124-E Yocle~'. E .I. and Wi~czak, Sons, Inc.. New Yc~'k. N Y. "Joint Design for Co~crete ]-li~hway a~:cl Associatkm. Sko~ie, IL Repo~'l No 2959 - 14- Ju~lc 30, 1996