引孔静压桩施工技术存在问题及对策研究

引孔静压桩施工技术存在问题及对策研究LeadstatiｃpiｌeｃonｓｔrｕctiｏｎteｃhnologyholeproｂｌeｍsaｎdcouｎteｒmｅasｕreｓTianＳhａoWei;China19smeltiｎgｇrouｐCo。,LTD。３１5807；Absｔract:thesｔaｔiｃpilebｅcauseofiｔｓmanyadvantagesｉｎtheｕｒbaｎcｏnｓtrｕctioｎａndgetdａｙbydａyｔhewidespｒeadappｌication.Firstlｙexｐouｎdｓthepｉpeｐilｅｃoｎsｔｒuctｉｏnｔechnology,ｌedtheｒeｓearchbackgrｏｕndanｄｓtudyｈolesｉgｎificanｃe，proposｅleａdhｏｌeｓtａｔｉcpilemeｔhｏｄｃｏｎsｔｒuctｉonmetｈｏｄ,tｈｉｓpapｅranalyzeｓtheａctuａlｃｏnstructionofｐiｌe,sｕｓpendeｄinthepiｌebｒeaｋinｇｐiｌe,tｈepｈenomenonsuchａｓallkindsofreaｓｏnsａndputｓforｗaｒｄthecorrespｏndinｇｓolutioｎｓandtecｈnicalmeasｕrｅsaｉmedatoｔheｒsiｍiｌarpｒojｅctｃonstｒｕｃtiontoｈａvetｈｅｃｅrtaiｎｒeferｅnceｒｅｆｅrenｃｅ.Keywｏrｄｓ:ｌeadtｈeｈolｅstatｉcpilecｏｎstrucｔionｐroblemsIｎｃｉvileｎgiｎeerinｇcoｎｓtrｕctionprocｅss,thefirstｔotheｆoundaｔiｏｎｃonstructｉon。Pｉlefounｄatioｎiｓconsｔruｃtiｏnespeciallyhighbuildingcｏnstrｕｃtionisｍoｓtcommoｎinthｅformｏffｏunｄatiｏn。Forｍatiｏnofｔhepilefoundａtionoftｈeprocｅｓstowｏrkwｉthｔhｅmｅｃhanicａltｏcomｐlｅtetｈepiｌe．Tｈesuperioｒｉtyofｔheｓtatｉｃｐressｕreｐileｇotｔhegeneraｌａgｒｅe,butwhencｏnｓｔrｕｃｔionhaｓsomemustoverｃomeｔhepｒｏblemaｓｏｉlcompactioｎefｆectonsurrｏuｎdingenｖirｏｎmeｎｔ，constｒuctioｎwoｒktｉmeboｄyｒouｇｈ,pilebｏdytilｔ,clippilｅbｒｅａkageaｎdpileboｄybreａｋ，airfrａｍeisｔoobiｇ，motoｒpeｒｆormanceispooｒ，ｉntelligeｎttestsystemblank,etｃ。Foｒhowtoｅｎsurｅｔhｅsｔaticpｉlingpressureｐiｌequalｉtyａndtheimprｏvｅmｅnｔｏｆthｅpilemaｃhiｎestｒuｃtuｒeisａseriesoｆｐroblems,ｓuｃhaｓpiｌeｍａcｈｉnｅdesiｇnｒesearcherscｏnｓtaｎtlｙtoeｘｐloreａｎdinnｏvate．ＮoｗiｓZｈｏngYehｏmebuyersnanjｉngｉｎhｅｘiLianＨuaCｕnfavouｒｉngovｅrｗhelminglyseｃtion1rｅsiｄｅntialａrｅaＡｂasemｅntcivｉlaiｒdefｅncｅ（ｂasemｅntsectioｎ）asaｎｅxampleforreｓearch1projectｓｕmmaryCｈiｎa19ｓmｅltinｇgｒoｕｐCo.,LTDZhonｇYｅbuｙersｏｆuｎｄｅｒtakeniｎhexiLianHuaCunnａｎjingｌow-cｏsthｏusｉng１rｅsidentiａｌareaＡsｅctｉｏnofｃivilairdefenｃebasemeｎt(ｂaseｍentsｅctｉｏｎ)，A0１＃～Ａ03#,B01#~B03＃，D01#～Ｄ0２#（residentiａlbuｉlｄingshave2ｆloorsｕndｅrgrounｄstrｕｃturereｓｉdｅntialbｕｉldingｓ，thehigｈestｅlｅvationfoｒ+98。９5０(ｒｅlativeｅlevaｔion),rｅｓｉｄentiaｌfｏundａtｉｏneｘcavationｌoｗeｓtelevationfor9。950(relativeeｌevatｉｏn）),ｃoｍmerciaｌ2~commercialｆouｒｔhflooｒ，nanｊinｇciｔｙ，ｊiａｎgsuproｖiｎcｅｉslocatedintheＪiａnYeOuｈeｘｉnewdiｓtrictbarsｔrｅetLiａnHuaＣunecｏnomｙaｐplicａｂｌeｒoomBgｒoupwｉtｈinＡping,nearthecityofｎａnjiｎgroaｄaｎdthenortｈJｉanＹeOuhｅxｉｎeｗdistｒｉcｔadｊａcentｔoｔhenａｎｊiｎgｓandbarsｓtreetＬianHuaCunｅcｏｎomyisappliｃａblehousｉngｉｓAgroup，eａstｎeighbｏurＮaHe,natioｎalｈigｈway205andaｄjacｅntｔotｈedimｎesｓｏfthｅplanniｎg,geｏgrａphicｕnitｂeｌongtｏtheYangtzerｉverflｏｏdｒightbａnk,fisｈｐonds,dｏｔｔedwithrivｅrｖalley.ＭaiｎfinishｆorcivｉlaiｒｄｅfeｎｃeａreａAｂasement(ｂａseｍeｎtsection)andsｉxbuildingsｏf34residentiaｌbuilｄinｇ（A０1～０3,B０１～03)，１26flooｒｓbuildｉngreｓidentialbuｉldｉng(D01),1A24／30lａyｅr(D０2）,3ｒesｉdｅｎｔialbｕｉldinｇAlａyer2busｉnesses（（2)—(4)),thesｔｒuctuｒeofｔheｂｕildinｇａndwatersupplyａｎｄdraｉnaｇeaｎdfiｒewatｅr,ｅlectrical，andｈvacaｎdｏthｅｒpｒｏｆessioｎalｉnsｔallationofcｏnstructionofthｅpｒojeｃt。Ｓiｔeｉseｒoｄｉｎgｔheｒｅsiｄｕalgeomorpｈicｕnits,thｅｆoundatioｎｓｏilsoillayｅrarefoｒaｒｔiｆiciａｌfｉllｉｎｔhepｒoductlaｙer（miscellａneousｆｉllinthesoiｌ，ｇraiｎfiｌlｉng）,ｔhefourthphaseｄeｐosｉtionｏfｌakepondlayｅｒ（mud）,thｅｆourtｈisneｗallｕvialｌaｙｅｒs(claｙ,theｍuddysiｌtyｃlay,siltyclay,ｓilｔｙandsaｎd,ｓiltysａｎｄlayercriｓscroｓsdｉｓtriｂｕｔｉｏnetc),etc.Ｉnthefｉｅｌdofgroundｗatertypeshaveｉsｄiｖing，poreconfinedwaterａndbｅdrｏcｋfissuｒeｗaｔerｔhreetｙpes。Divｉnｇoccurｉnartifｉcialfillinthepｒoductｌａｙｅr,precipitation,suｒｆacewatｅriｎｆiltrａtｉｏnistheｍaｉnsourceofｓｕppｌy;Theｐｏrｅwaterpresｓureiｎｔhefourthｏccurｒｅnceｏfnｅｗalｌuｖialｌayｅrsofsiltyandsａｎd,silｔｙsaｎd，sandaｎdgravｅlｉnlａyer,ｔheupｐerwａterｐenｅtratiｏｎanｄlatｅrａｌｓuppｌyiｓtheｍａinｓourceｏｆｓupｐly;Theoccurrenceofｂedrｏcｋfissurewaternｅxtvbedｒoｃｋrockfraｃturｅ。Divinｇstablｅｗaterlｅvelis0。０0~２.10mdepth,eｑuiｖaleｎttoaｂsolutｅｅlevation５。3０~7。3５m，ｔｈｅpｏrewaterpressurewiｔhｍｉcrｏconfinｅｄsex,itｉsｔoｂｕｉｌdｔhepresｓureheadｂurｉｅdｄｅep3.52~３。81m,equivalenttｏeｌevatioｎ3。20~4。２1m;Bｅdroｃkｆissurewａteroｖerallseeliｔtleｗａｔerａndｕｎeven.Thearｔificｉａｌfillintheｕppｅrｌaｙｅｒdepositioｎｍiｓcellaneｏusfilleａrth,gｒａinfillingａstｈｅunｃonｆinedaquｉfeｒ，goｏｄpeｒmeability,ｉtscｌａy,tｈeｍuddyｓiｌtｙcｌaｙ,siltyclａysoil,powｄerforrelatｉｖelyimpermｅabｌelａｙｅr，whentheｆoｕndaｔionpiｔeｘcａvationｄeptｈoｆ6.50m,theｆoundaｔionpｉｔwaｔｅrmaiｎｌｙfｒｏmmiscelｌａｎeousfｉllｉntｈesｏil,grａinfillingｄiｖｅ。Accorｄingtoｔheiｎｖeｓtigａｔioｎreport)，thｅaｒtifｉｃialfiｌlintheｐrodｕctlaｙermiscelｌaｎeｏｕsfilｌintheｓoiｌｏfthepermeａbiｌｉtycoefficｉeｎｔｏf6．20ｍ/d，ｇrainｆilｌinｇtｈepeｒｍeabｉｌiｔyｃoeｆfｉcienｔｏf０．３5m/d.Exｐlｏｒａtionｐoinｔbelｏwtheplanelocatioｎs:Meｃｈａnicaldrｉlｌinｇｐｉlemｅthodinprocessｉngplantbefoｒesoｍecitybuilｄｉngs，nｅａrbyｔheroａd,ｄｅnseneａｒｂｙundeｒｇｒoｕndｐiｐelinetoinfluｅnｃeandｐiletipthroughthiｃｋhaｒdclｉｐsoillayer,allhavｅmoｒｅsｕccessfulcｏｎｓtructionexperｉencｅ．2resideｎtiａlareaAbaｓｅmｅntcivilairdｅfence(basemｅｎtsection)bringholeｅngineeriｎganalｙsｉs２．1ｐrojectsurveyanddｅｓｉgncｏncｅｐtＰlannｉｎgdｅｓigntｒiestofｏllowtｈeｈumanist，ｔheｅcologｉcalｅｎviｒonmｅｎtｏptiｍｉzｉng,ecｏｎomicbenefitanｄsocialbenefｉtthepriｎcipleofeqｕaｌiｍｐoｒｔａnce.Fｕllconsideｒationｏfthelocaｌfarmｅrｓ’ｌｉviｎｇｈabiｔｓ，maｋｅfulｌuｓeｏfgoodconｓｔructｉoｎcoｎditｉon,ｆullyｅｍｂｏdiesｔheｍoｄeｒｎｉｎnovativｅandadvａnｃeｄideａ，ｗill“ｃiｔy，aｒcｈitｅｃtｕre,sｐace,thehｕmaniｔiｅs，theeｎvironmeｎt”fullｙthefusion,ｗillｔhisblocｋdｅsignbeｃometｈｅnewcenturybeｃoｍｉｎglargeraｎdmoｒestａndarｄFaｎHua,tｈｅecｏlogicaｌlｉvingcomｍunｉty.1)ｆorwａrdcｏmbinaｔｉon,ｆｕｌlｃonｓidｅraｔｉonstage,blocｋdｅｓignandｆeasibiｌityoｆthｅimplementatｉonoｆthｅprinｃiplｅ。2）modｅlvillａgｅfeatｕrｅs，ａｂａｎｄｏnｔhefancypｌaｎe,aｎdｐayingatｔentiontotheresｉｄeｎtialｈｏuse，arｃhiteｃturalformｗｉthurbanｓtyleandthｅcoｏｒdｉnａtionoｆurｂanstｒeｅtviｅw.３)theoptimizingenvironmentandｅcology,iniｍｐrｏvingtheｌａndｅcoｎｏmicbenefit,andｉｍprｏｖetｈeintｅrｎａlenｖironmｅntquaｌitycｏmmｕｎｉty,creaｔiｎgｇoｏdgardｅnｃeｎter,walｋｇｒeenbｅlt，ｇreennodeａｎｄriｃｈｌevｅlｓoｆlｉvingcuｌtureenviｒonmentspace.２。2geotecｈnicalengineeriｎggeologyｃondiｔionＩnveｓtigationpurposｅandreｑuｉrement：cｉvilａｉｒｄeｆenceｏｆresｉdentialareaＡbａseｍeｎt（ｂaｓementsection)thｅdetａｉlｅｄｓurvｅyforｔheｇeotechnｉｃalengiｎeering。Ｔhｅpｕｒposeｏfthesurｖｅyandrequirｅｍｅｎts：1）ｆindoutｂａdgeolｏgｉcaｌeｆｆeｃts，thｅtypesaｎdthecausｅｓ,ｄistriｂutiｏn,developmeｎtｔrｅｎdaｎｄhａrmdegree，pｕtfｏrwardtheSｕggeｓtionsreｎｏvatｉonｓchemｅ;2)finｄoｕtｗｉthinthescopｅｏｆthｅgeｏteｃｈniｃａlconstructiｏnｓiｔe,thetyｐeｓofｄeptｈ，aｎdｔhｅdistribution,enginｅeringcharaｃteｒistics,ａnｄanａlyｓｉsａndｅvaluatiｏnofthｅfoundatiｏnｓtaｂiｌｉｔｙ,ｕnifoｒmｉtｙaｎｄbｅaｒｉngcapaｃity；3)ｆindoｕtｏｆtherｉver，ditｃhburｉｅdｓhorｅ,grａｖｅ,sｈｅlter,suｃｈａseｎginｅeｒiｎｇｏfadｖｅrｓetosｅｏkjeonglaｎdbｕｒied;4)fｉｎｄoｕttheｂｕｒｉaｌcｏnｄｉｔioｎaｎdgrounｄｗater,changelａwofundeｒgrouｎｄwaterleｖelandｐrovｉdeｃhａｎgerangｅ,ｄeteｒmｉnetｈｅgｒoundwatｅrofbuｉlｄｉｎgｍateｒiａlsｏfcorrosive;5）dｉscrｉminantsitetypeanddｉscriminａntｓaｔｕratedsanｄliquefaction；２.3leadｈolehoｍeｗｏrkｃoｎstｒuctionpｒｏcedure(1)mｅaｓuｒingunreeling，dｅｔerｍineacｃuratelytｈeｐｉｌｅlocatｉoｎ；Uｎderstandｉnｇｔhepileiｓｈaｒdlayerburiedｄepｔh，ｔhicknｅsｓ;Ｈigh—ｐｒesｓureｒotarysprａyｄrilliｎｇemｐlacｅment，levｅlｉng,prepａrationbentｏniｔeｍｕｄ.（2)high—prｅssurｅrotaｒyspraｙdrillrig,aｎdlowprｅsｓuｒewatｅrinｊectioｎｔrｉp,wateｒｉnjectiｏｎprｅｓｓure20ＭPa.Thedｒｉｌlwiththesｉdｅsiｎｊectionholeａreａlｌｉnjecｔiｏｎwaterfｌow,eaｓｙtoｄｒiｌｌdｏwｎ.Leａdholepurpｏseistopｒoviｄeｐilingｔｈeholｅ,theｅngiｎeeringpｉｌesstｒonglyweａtheｒedgraｎiｔelａｙerssmoothlythrouｇhｔheｄeｐthtｏmｅettheｄesignｒｅquiremeｎts。Bｙｔhebｕｉlderｏfpay—oｆfdｅtermineａpｉle,andtｈeｃontｒｏlpoiｎｔｌeadtonｏtｔｏinterferｅwitｈthepｏsitｉｏnｏｆtｈｅdｒｉllinｇ,driｌlｉngａftertheｃｏmpｌｅtionofthｅpileｒeseｔtoacｏｎｔrolpｏintｓ，aspｉｌinｇbaｓis.3)ｖeｒtｉcaldegｒeecontrol：leadtｈeｈolesinｔhevertｉｃaｌdeｇreｅｄirectｌydeｔｅrmｉｎeｔhｅｖerticａlｄeｇrｅeoｆengineｅｒｉngｐiｌes，soverticaldegｒeeｏfｃontrolｉｓthekeylｉnk,eｓpeciallyafteｒpilｉｎgmａchinｅｉsinpｌacｅ,thefｉrｓtquartｅｒofｔhｅｄriｌlpｉpecｏｎtｒｏlshaｌｌbeapprovedbytheZhiAｎYｕanrｅviｅwqualifｉｅdreａｒｃanspud，everyincreａseａqｕarteｒafterreｖｉeｗofaｖerｔicａlpipｅ。4)intoaholequaliｔｙcontｒol：ｄriｌlingproｃessshｏulｄｂｅbasedｏnthegeologiｃａldａtａrepｏrtthｅｓitｕatiｏｎｔopaycｌoseａtｔentiontoｔｈｅsoｉlａndｗaｔerlevｅlｃｈanｇeｓｉndrilｌing，iｆdisｃoｖerthｅuｎdｅｒgrouｎdｈaveoｂstaclesshallbeiｍmediatelyｓｔoppedfｏotage,theｃausｅsweｒefoｕndoutｂｅforeyoｕmｏveontotｈeconstrucｔiｏn，sｕchasthｅcａｓeofｃoarsesａndsoilcｏnｔａiｎｉngｍoｒeshouｌdbｅtimelytoadｄtｈemuｄ,andthicksｔrａrｃｈcirculaｔion,ensuredonotproduceｈｏlecoｌｌapsｅphｅnomenoｎ，3leaｄhoｌesｔaticpｉｌecoｎstructｉｏnｍeｔhodｔｅcｈｎicａldｉｆfiｃｕltiesandcｏunteｒmeasuｒes３。１ｌeadapｉleholetｈeproblｅｍandｃounterｍeaｓureＴhemａinｒeasoｎiｓ:1)withｏｕttheｌevｅlingｏｆthefｕselａgｅ。2)ｔhegrouｎdbaｄflaｔnessorｌowｂearｉngcapaciｔy,easytocausｅtｈefuｓelagelostflat.３)ｔheoriginaｌsｉteforoldbuilｄiｎgdeｍoliｔiｏn，thｅbasalbackfilｌsｏilcontainsａｓmaｌｌamountｏfrubbｌe,ｂrokensｉlicｏnｐiece,ifpiliｎｇappeareｄintheｐrｏcｅssofprｅｓｓｕreriseoｒpileinvain；sｕddenly，itｍaｙbｅthｅsoｉlhａvｅirrｅgulａｒrｕbble，bｒｏkｅnsｉｌicｏｎcaｒbidebｌoｃkａndｓoontｈings,shａllbｅimmｅdｉatｅlystoppiling，usefirstａｒｔificialoｒｅｘcａvatordｕgｒｅaｒcancｏntｉｎueｔopileｔｈeprｅssurｅ。４）clａmｐmｏｕthoilcylｉndｅrsynchroniｚation,cauｓeemｂraceprｅssureclａmｐing，ｃlampmouthｓｕrｆaceｗｉllnotvertｉcal,tｈepiledeflection。５）pillａｒassemblyｐreｃｉsionloｗ，vｅrtiｃalｐａrａｌleｌdｅgreeｉspoor,guideｗhｅｅlanｄｒａilgａpｗiｔhirrｅｇularortoobig。6)guiｄewｈeeｌwearserｉousorinapｐroｐriaｔeposｉtionoｆwelding.7)pｒesｓｕreintheproceｓｓofpiｌｅ,ｐilｉnｇandpiｎｅpiｌｅsiｎtervａlaｃtionｓhort，pilingforｃehaｓnotyｅｔbufferunloading,ｃaｕsｅaiｒfraｍｅtogroｕndseveｒeiｍpact,whiｃhｌostthｅsｗingfｌaｔ.Sｔaticｐilｉngmethｏｄcｏnsｔrｕctionpiletｈeｔｒeatmｅnｔmetｈodofinclineｄ：ｔｈeconstructionofｔhｅlevｅliｎgoftheguaｒａntｅe。Inｔhepillａrasｓeｍｂlywｅｌding，ｔoｐreventthｅweldinｇdeformation,Wiｌliaｍgaｌlasｓtemguaｒanteepillａｒparallｅlｄegｒeｅbetweｅn,oｎagingtreａtmeｎtafteｒwelｄｉng．Ｔheclipｐilｅｂｏxaｓsemｂlｉnｇcａrｒytｏpillarmidｄlｅcoｒｒｅｃtiｏｎ,pａｒａlｌｅltothｅerｒordiｓｔributｉｏnｏnbothｅndｓtopｉｌlar，reducｅtheｇuidｅｗhｅelgｕiｄerailｇap。Cliｐpileoilcylinｄｅrsyncｈronｉzaｔion，causｅｃlａｍpiｎｇpilewithvertiｃalmouｔhaｆterclａmp，thepiｌedefｌecｔion.Tｏthiskiｎdofcircumstance，cａnpａｓsinｔheheartofsteelａddaｆterpaｄ，ａｎdaｄjｕsttheclampmoｕtｈgrａｄieｎtitself，sｏastoensuretｈatｃlippiｌｅａfterpilevertiｃal。Maｋeｐileendasfａraspoｓsｉbleｔｏtｈeｇｒouｎd，thenvertｉｃalcｏrｒecｔion．IｔwouldkeepｃｌｉｐｐiｌetiｌtAngleofthesｍallerbｏｘwhｅntｈepｉleｉntｏthegroundpressuｒe,tｈroughｔhｅｒoleofthepilｅtoaｓsisｔguaｒanｔｅecｌippiｌebｏxdon’tｔilt．Tｈepｒeｓsurｅｏｆｔｈefiｒstrootpiｌe,correctｉｏn，theuseoｆguｉdｅwｈeeｌandrailｇａpsmａllerpaｒtabout1/3ｐresｓurefiｒsttrｉp,pressｅdiｎｔothepileｓoｉl，aｎdtｈenrｅstarttheｖerticａlcoｒｒectiｏｎ。３.2ｌｅａdholepiｌｅafｔerpｉlesuspensｉｏnpｒobｌeｍTheactualimｐlantedpilelenｇｔｈisfaｒlesｓｔhaｎthedｅsｉgntｈｅpｉlelength，andtheｄｅpｔhoftheintｒoduｃtionａｎdmｏｒethａnthｅactｕaliｍplａnｔedthｅpilｅlenｇtｈ，ｃauｓingatｌeast1～ｉｎtｈｅ2metersforhanｇingpiｌesphenomenoｎ,tｈistｙpeofpｉｌｅlostmucｈoftherｅｓｉsｔaｎｃeandｆｒｉｃtionalresｉsｔaｎcｅ。Figure2holdｓｔaｔicｐｉlｉngｐreｓsuretｙｐeofconstrucｔionmethodｆｏrpｉlｅsｃｈｅｍesＢｏｔｔｏmｌinｅtoｏclean,resistaｎcebigger,totheｓeｄimｅntproblemｓ,becaｕseｐrevｉouslｙusedａ１50ＸYｃlearsｌａgmudpuｍpｆorcabinsysｔems,powｅrsｍallｅｒ，instanｔlyｐressure(ａbｏuｔ1。5MPa）eｎoｕgｈtotaｋeｕptheresiｄuａlsｏｉlunｄｅｒlｙｉngａndweatheredrockｏfquartz,fｅlｄｓparｇｒain，dueｔogeｏgraｐhiｃalrｅasons，thｉsfielｄｑｕaｒtｚ,fｅldｓparparticlｅｓalsosliｇｈtlybig．Procｅｓsingmｅｔhｏds:suchaｓborｅｄpileup，fｏradozｅnｐrｅｃastpiｌe，moｄiｆｙelevaｔedpilecapｓ,letｉtsｓharetheuppｅrlｏaｄs。Sucｈastｈecasｅｏfａcciｄentｓｃaｎaddtheｒootsoｆpｉlemeｔｈodｔodealwｉthｏrｕseaddｓｍaｌlstatiｃpilereinforcemｅｎtmeｔhｏd。Ｆiｌltheｐilesmｅtｈｏd,ｂｅcauseｐileeｎdｎoｔｅnｔerｉncｌuｄethｅｄesiｇn，ｏrpｉlｅｅｎdexｉｓtsofｔｌayer，ｃａnstaysupergaｐwaｔerａway，thetwopｉｌeendpointsoilｌateralｄisplacｅｍeｎtafterinｃｒｅasｅfromsideｔoside,aｎdtｈeｎusiｎgtheｓtaticpｒｅsｓｕｒeｍethｏdtopileｔheｐresｓureintothｅｄepthofｔhｅｒｅquｉreｍentｓ，andgiｖeｆuｌlplａytothebｏttoｍresiｓtａnceaｎｄthｅroleoｆthefricｔioｎalresisｔanｃｅbyiｎordertoａｃhiｅvetｈebｅaringcapaｃｉtyofthedｅsignrequireｍents.Ａfｔｅｒfilｌingpiｌeconstｒｕctｉoｎispressuremethoｄ,thatiｓ,ｉnthｅmouthofthecａveandanｃhorpiｌecaｐｓisreserｖed,usesｔｒuｃｔureiｔｓｅｌfａsastａｔiｃpilecｏnsｔrucｔｉｏｎcoｕnterforcedeｖiｃe,tｈiskｉndｏfｍetｈoｄiseasytoopeｒａte，cａnsideupperｓtrucｔｕrｅconstruction，filｌｓtｒoｎgfoundａｔionandｎotsideｅｘtenｓionoftiｍe.３．３lｅadafterｂｒeａkiｎgpiｌeholepｉleInaddｉtｉontｏprｅｓｔresｓeｄtｅnｄonspipepiｌetｈestｒenｇthoｆｔheoutsｉdｅthｅirowｎinadequate,ａlsoｄoｎ’tｅxpeｌbyｉｎtheproｃeｓsofpｉlepipeｊointweldinｇqualiｔyispoｏr.Thｅpｉpeｗeldingjoinｔｉspｉpeｐilebodyqｕalｉｔyweaｋｌinkｓ,wh