如何在樁基設計規(guī)范中定量考慮施工檢測的作用

XX大學,XX年XX月XX日

Constructioncontrolandsafetyofpilefoundations

如何在樁基設計規(guī)范中定量考慮施工檢測的作用

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xx大學土木與環(huán)境工程系1HKUSTContentsIntegratedesignandconstructionqualityassuranceProposeaproceduretoinvestigatetheeffectofconstructioncontrolonthesafetyofdrivenpilesProvidetheoreticalbasistoderivefactorsusedtoconsidertheeffectofconstructioncontrolindesigncodes2HKUSTConstructioncontroltestsoranalysesManytypesofconstructioncontroltestsoranalysesareroutinelycarriedoutasameanstocopewithuncertaintiesFinalsettestsDynamictestsusingpiledrivinganalyzers(PDA)WaveequationanalyseswithmeasurementsBlowcountanddrivingenergymonitoringStaticloadingtests3HKUST4HKUSTPDAtest5HKUSTExample:aseven-stepprocessforselectingdrivingcriteria

(Belletal.2002)1

Evaluatesubsurfaceandperformstaticpilecapacityanalysis2Selectpreliminarydrivingcriterionusingwaveequationanalysis3Driveprobe(orindicator)pilesacrossthesiteareaanduseaPDAtoevaluatecapacity,drivingstresses,andhammerperformance,includingre-tappingofselectedpilesafterinitialset-up4EvaluateandadjustthedrivingcriterionbasedontheresultsofthePDA5

Drivestatictestpile(s)usingthereviseddrivingcriterion6

Loadtestthetestpile(s)7Performafinalevaluationofthedrivingcriterionfortheproductionpilesbasedonthestaticloadingtestresults6HKUSTAllowablestressdesign(ASD)GeotechnicalresistanceDeformationRn=Nominalresistance(nominalultimatebearingcapacity)FS=FactorofsafetyQi=Nominalloadeffectdi=Estimateddisplacementunderthenominalserviceloadeffectdn=Tolerabledisplacement

7HKUSTFactorofsafetyAfactortocompensateforalluncertaintiesindesign,notsimplyafactorofstrengthreserve.Allfoundationmayfail!Theproblemishowlikely.FOSdependson:

RequiredreliabilityConsequencesoffailureUncertaintiesinsoilpropertiesandappliedloads

LevelofconstructioncontrolCost-benefitconsiderations8HKUSTFactorofsafetyandlevelofconstructioncontrol(basedonLikins,2004)9HKUSTLimitstates

Alimitstateisaconditionbeyondwhichastructuralcomponentceasestofulfillthefunctionforwhichitisdesigned(Withiametal1997).Strengthlimitstates(ultimatelimitstates)GeotechnicalresistanceStructuralresistanceServicelimitstates(functionofstructureunderexpectedserviceloads)Deformations,vibration,cracking,localdamage,deterioration(durability)10HKUSTSomeultimatelimitstatesforfoundations11HKUSTProbabilitydensityfunctionfQ,fRQ,R_Q_RAreaprobabilityoffailureLoadeffectQResistanceRProbabilityoffailure,pf

=P(R<Q)ConceptofreliabilitybaseddesignMeanFS=/NominalFS=Rn/Sn_R_QQnRn12HKUSTLimitstatedesignUltimatelimitstates(MOC2002)Tobecheckedindesignofalltypesofstructures&loadcombinationsServiceabilitylimitstatesTobecheckedonlyforimportantordifficultfoundations

13HKUSTGeotechnicalresistance:

Servicelimitstate:

(sameasASD)

Rn=Nominalresistancef=Resistancefactor,asafunctionoflevelofconstructioncontrolQi=Loadeffect

gi=Loadfactor,definedinsuperstructuredesign=Factortoaccountforeffectsofductility,redundancyandoperationalimportance,>0.95di=Estimateddisplacementunderthenominalloadeffect(ServiceIloadcombination,gD=gL=1.0)dn=TolerabledisplacementLoadandresistancefactordesign(AASHTO)14HKUSTTargetreliabilityindex(MOC2001)

UltimatelimitstatesFailuretypeGeotechnicalcategoryCategoryICategoryIICategoryIIIDuctilefailureBrittlefailure

ServiceabilitylimitstatesbT=0ifthedisplacements,cracks,localdamagesetc. causedbyloadeffectsarereversibleafterthe loadeffectsareremoved.bT=1.5iftheseserviceabilityindicatorsareirreversible aftertheloadeffectsareremoved.15HKUSTResistancefactorsforgeotechnicalstrengthlimitstateofaxiallyloadedsinglepiles(fromAASHTO1998)16HKUSTValuesoflvforvariousmethodsofpileconstructioncontrol(fromAASHTO1998)17HKUSTReliabilitymethodtoconsidereffectofconstructioncontrolEstimateempiricalstatisticsofadesignmethodReducethevariabilityofthedesignmethodgiventheoutcomeofacontroltestoraseriesofcontroltestsObtainnewstatisticsofthedesignmethodObtainnewpartialfactors/resistancefactorstoachievetargetreliability18HKUSTUncertaintyofdesignmethods19HKUSTBiasfactorandcoefficientofvariationforvariousdesignmethods*Note:20HKUSTWhat賺hap輪pens厘if餐test宵pil桐esp憂ass冊cont踐rol副test紀s?–床Bay鎖esia伴nre木gres悼sion笛ana舍lysi冤sx=m售eas稅ure糊dp魯ile尾ca物pac裹ity捎/pr殼edi末cte矩dp阿ile斤ca膨pac挪ityxfol最low歪sa錫lo宣gno惕rma禮ld勉ist鑒rib登uti桂onEmpi辰rica憑lst衣atis狹tica聾lva真lues鄙ofxmeanmsta仁nda掙rd拋dev管iat累ionsTake灰the眼mea閣nmas撤av書ari翁abl處eAp件ile雙pa族sse駐sncon捆sec溪uti桌ve安con濾str恭uct湊ion矮te吳sts袍atx=xT,t通hen餅th外ep駕rob麥abi秘lit算yt謠hat漢al雁lo垮ft脹hentes辯tp犧ile售sd宿on燒ot嘉fai談la影txTis(蹦Zhan揀g,2工004)娃isThe寇di今str側ibu紗tio畏no菜fxist忠hen具upda塌tedUpd漂ate亮ds般tat嘉ist染ics怠fo鍛rx:l攜arg粒ermand斬smal案lers21HKUS諒TExa于mpl立e:告Des萬ign常ba如sed連on高a裁SPT夾me奔tho洗d(為Mey息erh繪of內197底6)姨and蜘ve殼rif僚ied類by扣pr雄oof課te仆sts結at拌tw橋ice非th楚ed高esi怕gn槽loa炭dlR=1個.30COVR=0.半5022HKU恰STExam灰ple:Upd獻ate貪db蛾ias呀fa輔cto漏ra啊nd雄coe念ffi全cie稅nt廉of贊var街iat右ion逗as以fu歪nct純ion年of就pi納le勒cap荷aci鄙ty23HKUS拳TCal悠cul紹ati汗ng筒res共ist孤anc惹ef鐮act嫩or懇bas倍ed沿on弓upd裳ate罵dp被ile哀ca兇pac煤ity笛st邀ati男sti術csCOVR,CO敘VQD,a土nd設COVQL=c族oef湯fic邪ien礦ts紡of兄var丟iat港ion疫of牌re淡sis哲tan桃ce托R,廚dea絞dl宇oad騎QD,an尿dli巴vel蕉oad雅QL,re刷spec酸t(yī)ive賤ly;lR,lQD,a特ndlQL=bi服asf張acto效rso蜜fre尤sist授ance途,de少adl凡oad,鏡and王liv許elo刮ad,梨resp華ecti直vely惱;Dand睡L=lo燥adf度acto捧rsf逼ord暴ead稅load滿and意liv銷elo附ad,貌resp吳ecti里vely柔;bT=ta堆rget擋rel信iabi限lity萄ind望ex24HKU杏STEff滋ect殺of丘co杏nst新ruc錦tio巖nc蘇ont釘rol墨on譯sa蜓fet率yf譜act器orReq角uir派ed榴fac技tor奏of腐sa返fet澡ya家fte俱rv胖eri葉fic役ati賠on阿by效dif狼fer嗓ent啊le洞vel濁so篩fc肅ons它tru傘cti組on和con灘tro園la介tbT=2剛.025HKUS右TReq槳uir牛ed繪fac控tor欠of門sa拘fet歇ya渡fte拐rv勾eri軟fic滋ati澤on娘by慰dif閥fer湊ent跌le平vel掀so慶fc本ons支tru膽cti筍on躺con詢tro明la彼tbT=2.賄5Eff靜ect浴of弄co域nst酬ruc臣tio叫nc拉ont在rol剛on結sa嬌fet巾yf繡act膀or26HKU棄STThe陳requ鴨ired幼FS姥can拆bes猶ubst結anti壞ally份red足uced護thr棵ough墓car熱eful味con濕stru芽ctio梯nco撓ntro完l.T掉her血equi戲red掠FSc憑anb夫ere河duce廣dfr勵om3碧.50晨for販the租stat買ica劇naly熱sis憶meth匆odb自ased慮on鋼the盲SPT辰to1電.42辦atbT=2.獲0,a順ndt勸o1.揉80a錄tbT=2幕.5賽for荷th弦es勢ame御an瘋aly迷sis盼th候at慶is放ver但ifi北ed頂wit慈ht傅wo俘CAP燙WAP迫an擱aly學ses端pl展us鋪two改st奶ati倡cl針oad槍ing乖te裝sts蕉.The頁re跳qui食red燃FS鍋de屆cre區(qū)ase趕sw費ith嚷th潤el答eve赤l(xiāng)o釋fc孕ons近tru裂cti琴on左con娛tro精l.制For炒in亦sta刺nce既,u濁sin栽gt蠢he俊SPT粱me努tho旋d,尋the瞞re栽qui儉red穩(wěn)FS銳st眠or域eac取hbT=2.足5ar相e2.壇24,浴2.03填and開1.8襖0,r移espe蒸ctiv罷ely爆afte地rve扶rifi淘cati港onb察ytw罪oPD宏Ate忠sts,震two蒙sta征tic旗load終ing描test蕩s,a較ndt壺woP淺DAt繩ests喜plu緞stw遵ost殼atic板loa肯ding寫tes昆ts.The愉requ繭ired困FSs片for背dif善fere抬ntd斧esig境nme琴thod獲sto麥rea久cht虛her甚equi辟red糧targ亡etr懂elia揪bili陳tya瞞red杜iffe規(guī)rent游bec鴨ause寺eac滴hme昆thod道is利asso遍ciat蝕edw行ith攀diff械eren嫁tbi趣asa蜜ndC消OV.胞Thus早it幻玉isn炊otr臘easo夾nabl估eto副spe昏cify唯the展sam伍eFS遷for木dif胳fere辭ntd墳esig疑nme纖thod碎sif唱the服sed廳esig電nme狹thod商sar萄eno謝tsu距ffic窯ient蠢lyv鞋erif可ied攏byc身ontr件olt腹esti蠻ng.Afte電rve相rifi貝edb嗚ysu轎ffic搞ient弊con薦stru哈ctio單nco如ntro貴lte呆stin哈g,t陣her賤equi遵red墊FSs偷for幕diff勁eren騙tde故sign物met么hods猴are片not繞sen助siti蠟vet歌oth脹eac議cura脊cyo岡fth航ein鬼divi繁dual暴met晶hods呢.Fo沙rex壺ampl目e,t溉her琴equi墓red嫁FSs延for約the神five料des添ign蛋meth扣ods桿afte寸rve祥rifi否cati趨onb筋ytw帖oPD形Ate綁sts咳plus稅two刮sta賊tic挪load趕ing繳test辯sfa拜lli蜻nto儉narr開owr島ange側s1.爛44-1吵.55摩and有1.80鬧-1.8手8.27HKU房誠STEff范ect傭of吊co塵nst刊ruc射tio詞nc弟ont毀rol怠on覽re溝sis胖tan薦ce香fac天torRequ呢ired挽res畏ista撐nce討fact此ora扎fter戶ver道ific咱atio朽nby賄dif抽fere鏟ntl見evel成sof蒸con堆stru目ctio蝴nco屠ntro芝latbT=2.浸528HKU沉STThe欠re擴qui德redfincr晶ease東swi栽tht哥hel駛evel伴of為cons只truc彩tion秘con跨trol行.Fo鑒rth蒜ede壁sign挖bas舉edo紀nth妥eSP圖Tme繞thod衰,th限ere嫂quir琴edfafte惜rve仿rifi儉cati拔onb仆ytw脾oPD尖Ate誤sts嫌only師,tw跟ost調atic蠢loa嘩ding訴tes驗tso袖nly,杜and每two隸PDA慢tes蝦tsp補lus披two參stat敲icl歸oadi罷ngt息ests硬are設0.6嫂1,0公.69,累and午0.7殿5,r采espe酒ctiv舌ely.Afte拳rsa竹tisf斑ying氣suf壇fici綢ent從cons開truc請tion美con川trol盆tes叔tso勒ran腎alys氏es,毫the彩requ咽iredfvalu漆esf渾ort滲hef愚ive等desi紹gnm性etho耐dsa斥ren裙ots個ensi霜tive鐮to嚴the墓accu鈴racy羽of關the茄indi晚vidu犁alm搶etho季ds.爸For離inst克ance駁,af逃ter艦veri乎fica蓮tion梳by途two奇PDA遣test艦spl忍ust甚wos凡tati粘clo克adin獨gte仍sts,濕the棗req饑uire體dfval拳ues義fo擦rt淚hes怖ed勝esi神gn貍met幸hod萍sf租all值in乞to仿an屑arr裕ow筆ran息ge衛(wèi)0.7論2-0欺.75巖.29HKUS袖TVal騰ues荷oflvafte鵲rve撲rifi回cati陣onb件ydi遲ffer愛ent艷leve貫lso糞fco迫nstr及ucti拖onc禾ontr箏ola爽tbT=2.狡5Note宮:Ta館ket校hose房誠wit叫hCA悔PWAP庫+Loa鞭dte鋼sta奶s1.健0030HKU猛STReq題uir牲ed里fac塑tor席of扭sa斧fet厲ya預fte覆rv個eri筋fic棗ati噴on繞by魔dif怪fer棟ent噴co嚴nst犯ruc涂tio車nc娘ont粉rol旅me虛asu責res31HKU婆STAse很xpec進ted,血the翁req巴uire永dFS援dec京reas址esw責ith性the微numb扭ero禍fco孩ntro旦lte視sts捆ora臥naly爹ses,膀par蘭ticu剝larl當yby亡the財fir拆stf秩ewt指ests鄰or就anal叮yses更.Aft怒er打sat藝isf銹yin野ga姑su漆ffi拒cie笛nt篇num蛇ber春of另co耳ntr嚴ol降tes換ts何or埋ana仔l(wèi)ys悉es,降th他er任equ才ire濤dF狗Sv估alu稀es圍for緒al蠅lt汗he泄fiv必ed槍esi狠gn拒met疊hod彼sa嫂ppe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