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Park West CC(15.1)-CS 941118--NOU-18-'g4 FRI 15:59 ID:REED ENG. GROUP tEL N0:214 350-001g ~80g P02 lto~r lit 1994 H~O~ee~.. No, 1920 pro~e deltgn group, ln~. 2607 #elnut Hill lane, 8uite 100 Dallaeo Texas 75229 Lone Star Plywood Airlinm Drive COPl~ll, Texas D~ar Nar~= Submitted here ars recomuondations regarding equivalent pavement · eotion$ for the refereneed project. The standard pavement was oonsldered to consist off 6-inuh thiok, 3,000 pounde per nqunre inoh (poi) oompressive strong.~h senators over 6 inohea of lime- stabilized gubgrade. Tho M%nlysls hue oonetgted of determining the daily repetitions off an equivalent la-kip axle load and a 20-year design Xife. TAe analysis golXowe~ procedures Zrom the American Association of State HI~A~y 0gf£cia~a (AASHO) Xnterlm Guide, A copy of the AASHO design nouograph is attached es Plate 1. Three pavoaent sections have been analyzed; the referenced wotandlrd# pavement, $ i~ohe$ of 4,000-psi concrete, and ? inches of 3,000-poi concrete. T~t latter two ~ectiona ware analyzed considerfng natural or u~abiliz~ The first factor to be derived consists of the modulus o£ subgrade reaction, k, for bo~h the natural subgrade and on top o£ a six-inch layer of l~me stabilized. A value of 100 pounds per cubic ~nch (poi) is recommended for the natural aubgrade, corrola~ions developed by the Federal Aviation AdBinimtra=ion (FAA) £Or oemen~- m~ubtltled aubqrade provid~ an e£fect~vs k value, considering a 6- lnoh stabilized subgrade o£ 210 pci. Two hundred pcl was used for tho analysis. A copy o£ the FAA correlation is attached as Pla~e 2. 2&24S'I'U'rZ DRIVE · SUITE 400 · ~ TEXAS 75236 · 214/360.5800 · (FAX) 214/35043019 NOU-18-'94 FRI 15:57 ID:REED ENG. ~ROUP TEL N0:214 350-0019 ~809 P03 migl~ grou~, inc. No. ~920 Novmr 18, 1994 ~ seoond rioter required to evaluate the #ctione consists of the vorkiH Itrell of the ¢onorete. T~il value ie e~uml to 0.75 p~roent of ~he modulus of r~ure (~). Correlat~ ~w~n the c~ress~ve s~reng=h and ~ indicate that the~ can ~ · ~r~. This analysis results in a worki~ ~trell of ~70 and 425 ~i Eot ~e 3,000- a~d 4,00O-psi concrete, reactively. Al~lio~tion of the AABNO homograph results in the derived ~iuiv&lent 18-kip axle loa4~ show~ ~1~. 6-1n~i~, 3,000 ps/ concrete over 6" lime 40 aN, 4,000 pli conore ~e over natural subgr&~e 40 7", 3,000 psi concrete over natural subgr~e 7O B dllaUlled above and as ~kown on Plata 1, the allowable daily tr&££i¢ Il based on a 20-year design life. ~en~d on thie analysis, G inches of 4,000-pmi ooncrete over a non- ll~-~tabilized subgrade i~ the equivalen~ off 6 ~no~es 0£ 3,000-psi oonorete over 6 inches of l[me-etabilised sukgr&de. arise, do not hesitate to call. If any REED Id F. Reed, P.E. oopies submitted: (~) NOU-iS-'94 FRI 15:58 ID:REED ENG. BROUP TEL N0:214 350-0019 ~809 P04 I ~ OF RIG, lO Ht01-1WA¥ PAVI~$ ;:' ;: !:..' strate the ~ensitivity of the factors. It can be seen that the method is sensitive to tra~c and quite sensitive to the stren~[th of the concrete itself. The modulus 6{ 'j' sub,fade reaction has a relatively minor effect. These data are £or ~parnttive purposes ami must be viewed with some caution, since experience has showll . '.. that the unktaown= o! variability (Ghapter !,~), .'md the tenuoui metluads o[ esti- mating trll~ (Ohapter 4) many times completely override all o{her consideratioq~, ', paveme~ Fijur for hil~ has joir. t~linIl of the ] It is i ~v{~ slab i~ ~t o~ v~ ~o . ~ultir ~ry to ~a vel At ti ~ure t nmoun ..- NOV-18-'94 FRI 15:58 ID:REED ENG. GROUP TEL N0:214 358-8019 .. , . . :,...~.,'~,.,,~ J~'.~i..';.'.:.t,:. ,,'-, ~809 P05 AC 1M/$320-6¢ ~2/7/70 4O0 3OO IlO0 YO I0 I0 lf~ 14 16 Il 20 22 ~4 26 fe 30 · I I I_ I I I I I I I · f~ 6 ? i IJ lO II 12 THIOKNESS. OF J~4JASF_, - I00 - 90 - lO - ?0 - IlO - SO ' 40 - 30 -IS - 2O 15 PLATE 2 , . '[ NOU-18-'94 FRI 15:59 ID:REED ENG. GROUP TEL N0:214 ~50-~19 ~809 P06 L:Z/7/7B AC l~O/5~20-6C (2) 0,) Cc) The evaluation requires the de CamA~aCion oil the tho ~t Xa~era, the fXexural strength o£ the cosut~mte, aud the meduluo o£ oubsradm reaction, (a) aviiZdKe from couaCruct~on ~COrda, Whe~e is mmC mtlEWle oF of questionable accuracy, may bm dmtecuiumd by bortnaa or te~C pica in the past .. (b> ~ a~ Cmt~ ~ ac~rm ~ ~ C-78, 5Md ~ m e~i~ to obtm~ ~d c~a. /ucu~d ~ ob~~ suf~i~imC n~ro of ~m to eet~i~ a re~tatiw s~le ~ ~ pr~iti~. C~tr~ion raa~ ~ be md m a oo~ of ~te ~e to ~ ~t~ for ~ ~ conch'ce mt~gh iue~ ~th ti~, I~c~h~ ~atio~ can ~ f~ ~ Port~ ~t ~mocia~, ~~ri~ B~~, ~et~ of ~cwete ~rt ~a~t. at~ and glex~al st~th e~s~ a~d cm ~ c~ed by ~ fo11~ f~a. compressive streasth stum~ and cemprommivo ocrmm6th or tensile mplittiu~ are paz 91' -'," REFERENCE