ConsrucionSaemenforVC真空预压发处理软土地基施工方案

ProposedDesignPhilosophy,Construction,InstallationandMonitoringMethod(asper22.1.7ofsection1.0)SourceofborrowspitindicatingthelocationandquantityWehavelicensegivenbyVietnamauthoritytoexploitaquantityof8,400,000m3inNhaBeriverandthelocationisinNhonTrachdistrict,DongNaiprovince.PhysicalproprietiesofproposedfillmaterialThesamplingtestofsandproposedtouseiscarriedoutaccordingtoAASHTOM45-89,C144-88(seeTestResultofAnalysesofSandcomponent).Thespecificweightofthesandis2.634,unitweight1.5g/cm3,organiccontent2.87%andmodules2.52.3.Proposedmethodofstatementandmonitoringdevices3.1MethodstatementAccordingtothegeotechnicalreportofthesite,thevoidratioofthesoftsiltyclay(e)is2.377,andthepermeabilitycoefficient(Kv)5.5*10-7cm/s.Ifweadopt“wickdrainsandpre-loading”methodtoreachasoilbearingcapacityof50Kpa,75Kpa,100Kpaunderthesite’sconditions,theconsolidationperiodwouldbefarbeyondtheproposedworkperiod.Forthepurposeofreducingtheconsolidationperiodoffoundationsoilanoverloadshouldbeadded,thoughtheloadingwouldbe7.30mhightofulfillthebearingcapacityof100Kpa.Obviously,thistechniquewouldbearatremendousnumberofloadingandunloading,whichwouldalsomeanahighconstructioncost.Thestabilityofsideslopewouldalsobedifficulttomonitor.BasedonourpreviousexperienceofsoftsoilimprovementofChinacoastalandHiepPhuocPowerPlantinNhaBe,15kmSoutheastofHochiminhCity,thepre-loadingmethodisappropriateonlyforgeneralarea.Inprocessareawesuggesttoadoptedthefollowingmethod(detailsseedrawings“ProposedProcessAreaPlan”and“ProposedProcessAreaZone”inpage6,7):易f迈=说50桨K没pa赢,鸦va五cu饿um愿p熄re稀co峡mp乏re截ss翠io任n逼me旅th种od幻;征f书=晋75色K泰pa灵,头va猪cu住um艳p歼re蛾co恶mp奏re节ss编io五n寸an估d己fi声ll锦in证g默wa碎te仍r脉(2旨.0障m)肃o睡n尸me内mb期ra棋ne盒m书et拔ho修d;京f萝=虹10扶0甘Kp冰a,优v鸡ac期uu休m访pr妻ec涂om拒pr牢es重si务on扩c抵om寇po蹲un亡d晃wi懒th扫l淡oa匹di昏ng租m切et跨ho会d.峡Th碗e义hy彻dr躁au秒li心c愁fi番ll迹in佣g株of常s胃ea渔s欠an莲d挠sh培ou瓜ld胶b胀e膀ad翠op狠te俗d离un教de陕r吼th刃e群el绝ev羊at散io漏n逐+2兰.8册0,慎w逗hi号ch框i盏s啄sp惰ec彼if瓣ie旧d默in芬t摩he拉t爆en迈de佣r锈do钱cu牧me丛nt府s.拳B颜ut炉b叫as潜ed录o由n是ou禽r五si锅te泪i及nv付es插ti烦ga商ti屋on罩r顾ep水or若t,饰w浪e头pr盟op戴os返e串to绵u倒se碧s很we蔽et绢w摸at杆er附s私an袋d嘴in屯st泊ea乖d辞of本s奸ea辨s河an狭d赶fo却r亩th晒es纵e拘fo街ll高ow兔in报g迈re心as盾on杠s:俘Fi畜ne雕g虽ra层de寻a窃nd闻h浸ig抓h复mu茧d尽co脊nt琴en拦t置of味t饰he屋s默ea撞s诞an驻d;踏川No祝l按oc斯al胡f趴ac灯il陷it竖ie清s卧av饭ai骆la驻bl拿e错su顺ch估a脾s考hy虏dr俭au唤li香c返fi宽ll陪in滨g书mu膜d足ab俊so吊rp爱ti室on驾.脂Th莲e换ba江ck依fi都ll批m析at聋er滔ia淹l童(s翁we廊et街w巾at港er限s腊an庆d)抱w脖il浪l茄be妖d容el交iv按er摔ed索b怎y心ba父rg牲es驰t收o第th服e柳ne律ar仰es睛t打do必ck幅a俱nd同t您he浸n亦ca窝rr斤ie酸d仿by槽t滑ru惹ck灾s逝to滑t且he货s形it款e.点3.奉2炭Mo宣ni远to皂ri钉ng险d禁ev母ic栏es察Ac崭co万rd雁in类g师to毛t雀he偿r亩eq越ui毅re衡me乓nt偷o锻f排th步e佩te崇nd那er阴d精oc器um控en钓ts箱,垦se滔tt柴le休me戏nt碍g脏au奇ge痰s芳ho雁ul呢d挪be迎i饺ns当ta访ll造ed清a耻t盟50稿mx办50赖m犯gr北id随a刑nd沙b罢e李me壶as催ur唇ed纽b折y想le削ve欣li患ng架i比ns描tr鞠um误en杰ts茶.虫In泛a如cc达or万da聪nc等e剥wi伪th糠t格he保r减eq趋ui叼re蹈me砍nt窑o饲f先th浅e赔ow无ne坚r,允t痛he雾s侵ta探ti坐c坝pe绍ne惧tr冈at筝io汇n蓬te阿st蹈s舅ho蜜ul碑d津be菊c惩ar捎ri清ed秘o职ut切a袍t休th供e仔10滚s稼pe狐ci办fi挎ed蹦p游oi谋nt浓s虚an排d法th古e星pe斧ne搂tr乡at协io摧n堪in围st劲ru款me怕nt尾s信sh惩ou悬ld私b声e懂bu煤ri割ed惩t狮hr阶ou跟gh罩t经he满w消ho池le各d陆ep讨th吉o厉f绞th拐e撒co每mp席re计ss坏ib截le泽s伐oi妥l慢la暗ye腹rs钩.艰Th拐e上co蹈mp堡ac天ti满on站t击es稀t标of税f恒il悄li鹿ng片m赚at番er愿ia勒ls卫i汁n却si缎te别s忌ho仓ul习d睬be慨c极ar种ri厦ed威o痕ut谅w恭it独h慕he混av污y态co盲mp谱ac漂to刺r.碎嘴De绘si轻gn甜p拿hi风lo面so诸ph锈y陶to群a裤ch佛ie峡ve五t扛he苏r搅eq录ui牛re默me蜡nt东o瘦f恒th样e斥sp鲁ec便if择ic初at符io丘n仗fo耗r册so妥il坡i诊mp援ro标ve艺me远nt旦ph丙il吸os句op阀hy非o衬f氏va汪cu具um肢p鸦re闹co鸽mp收re卷ss纽io揭n甩me制th得od末Th苦e椅va上cu解um鼻p玩re拜co桂mp凝re桨ss满io描n陈me罩th梅od瓣i间s华us府ed济t禽o滋co鸟ns轧ol偷id佣at天e逗fo芽un垒da帽ti副on绒s愿oi贷l.斧窗Th贝is旦m涉et晨ho喂d倚co回ns蠢is练ts祥i块n攻la祖yi躲ng件o蓄n帐th擦e蛮su向rf絮ac貌e山of熟f访ou念nd虑at棉io慈n辽so薪il头a摧s宣an危d拥be私d,雁a锈nd请i佛n蝇in烦st含al繁li植ng乘a乔d速ra较in恳ag腿e晕sy证st采em形w卷it静h秒wi缺ck弃d学ra嗽in目s.歉T拒he魔s乒an反d情be标d赚dr跪ai姓n柱li杆ne达i注s照bu接ri警ed嗓a如nd街c许on叠ne抹ct墙ed票w赤it可h铲va铲cu授um仔s船ys丢te棕m验to楼f战or罢m中an厦a怪ir想e蛙xh酷au纤st申a承nd哄a臭d纪ew证at侦er轨in卡g酬sy秘st北em鸦.绳A旦se洋t督of逼a预ir轰ti案gh纺t络se键al顺m腿em泛br帐an杰es数i心s闻la变id质o树n社th钳e档su俭rf咏ac项e胀of残t轰he绘s呢an鸣d触be沟d场wi纵th磁i拆ts纺e真dg室e停bu甲ri驰ed眼i流n筑so叛il突.扰Th色us挂,童a浴ne知ga窄ti充ve晚p霸re悦ss旷ur搏e忘ar僵ea常w桌it嫩hi正n榆sa封nd邻b票ed焰a巡nd发f案ou岔nd替at寿io鸣n冬so狼il押c胸an养b未e蝶fo湾rm旺ed糟f惭ro守m王ai当r硬ex浪ha贪us非t劈an截d己de截wa休tu禁ri遍ng盛p追um惠ps拜.偏Th酒e疑va数cu乡um赌m止et勉ho被d奉ca陶n胖re蝶ac膨h井a迟so出il净b林ea覆ri唉ng念c裳ap梅ac兰it所y滨of袜8羡0K识Pa惰.旋Un轻de赏r范th及e风va尾cu诞um蚁c朝on伯di堤ti免on袖,之so庙il筒i腊s菜in夹t恒he旱s帐ta闲te火o宰f糖co孙ns项ol忘id策at插in春g桃an或d阁po旺re敞w属at蹦er听i歉s捡di旷sc催ha挂rg桥ed难f即ro惩m米so蚂il晓u减nd居er旧t燥he吃p扬re摇ss币ur昼e国di为ff五er吸en麦ce摇.卖Th玩e攻co霸ns际ol宏id督at黎io坦n县is线c齐om疮pl元et深ed量w板he割n酸pr部es挠su排re愤o赶f紫so吃il判t寺o慈be新c卸on拣so值li汇da袭te凶d笑is音r坦ea疮ch侨in楼g颈th痛e做sa榨me下p招re恳ss财ur聪e饼of轻t鲁he镇d币ra呼in焰ag亲e健sy稍st呀em猾.焰Th者e蛋ph肆il健os疑op围hy稼o拖f徒va党cu死um样r率ec的om说pr胆es成si报on期m指et倚ho膜d核is太t教ha兴t催un铜de金r旷th叮e借pr鸟es袖su泰re什d仆if窜fe的re滩nc示e灾(虹P视a谢-P林v垃),师s烈oi战l弦ca稳n私be妙c修on舅so跌li酱da厘te劲d;吸五P秩a立i女nd糕ic弊at示es庭a贞tm赞os骆ph岂er互ic惕p对re傲ss贫ur弊e吃an竿d水P望v瓣i轰nd冬ic监at丰es猎a只ir妄p飞re炊ss逆ur旗e筒in泡t证he赌s斑an咱d御be刘d英an砍d搜th艺e摆ve拌rt芬ic劈al辩d嘉ra碍in湾s.只I寒n天th庙e循ca渔lc炊ul稠at桶io显n城of茎c色on鼠so北li码da逼ti购on港o门f茂th寺e耻fo飞un淋da磁ti码on刷s秘oi葵l,流t柳he竟R晨EN释DU腥LI寇C-甲TE兆RZ柴AG竿E则Th灵eo墙ry咱a饺nd缩B阴IC悼OT遍T惯he高or和y哭of恰C障on馅so斯li胃da糟ti雨on满c水an爆b贪e蜻ad登op寺te叫d馋wh汗ic恢h干ar羽e债th输e不sa纲me敞o投f碧th掠os拆e涛ad惹op长te金d格in腔l缝oa敏di漂ng俱r爷ec跌om辽pr开es拦si坟on饭m康et鼓ho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singeneralarea:L=1.20mForprocessarea:f=5t/m2,L=1.2m.f=7.5t/m2,L=1.1m.f=10t/m2,L=0.7m.Theinitialgeotechnicaldesignisshownintwotables:“GeotechnicalDesignofVacuumPrecompressionMethodofProcessArea”and“GeotechnicalDesignofPre-loadingMethodofGeneralArea”inpage11,12.ProposedverticaldrainsmaterialsTheSPB0-IItypeverticaldrainisadoptedfromCHINA.TheproprietiesoftheproductionmeettherequirementsofChinesestandardDB3201Q18-87(detailsisshownbelowintable“QualityStandardofSPBVerticalDrains“).ualityStandardofSPBVerticalDrainsParameterUnitTypeRemarksSPB-1SPB-2SPB-3MaterialsPlasticstripcorecoatedwithamembranefilterSectiondimensionsWidthmm100210021002Thicknessmm3.54.04.5Longitudinaldraincapacitym3/s15*10-625*10-6Sidepressure350KN/m2TensionstrengthKN/10cm>1.0>1.3Elongationis100%Elongation<10<10Permeabilitycoefficientcm/s5*10-45*10-4Capacityofinsulatingsoilm<75<75TensionstrengthofmembraneDryN/cm>15>30Elongationis10%WetN/cm>10>20Elongationis15%Linearweightg/m90-10090-100Unitlengthm200200SiteclearingSiteclearingGeotextilelayingPreparationofwickdrainsinsertingequipmentSiteofficeandcontrolcenterVacuumpipesinstallWickdrainsinsertionSecondsandbeddingFirstsandbeddingMembranelayingAirextractingequipmentVacuumgaugeandrelayinstallAirextractiontestPrecompressionbyairextractionVacuumpressureandsettlementreadingsintheprocessareaEquipmentremovaloftheprecompressionmethodRefillandlevelingWeirconstruc-tionControlandoperationcenterElectricalandlightcircuitRecheckthevacuumpumpsTemporarywaterpumpsinstallationVacuumpipepreparationMembranepreparationSettlementgaugesInitialreadingofsettlementandrelayResiliencereadingofgroundsettlementLeakagerepairofmembraneResultsverificationFlowDiagramofVacuumPrecompressionMethodGeotechnicaldesignofvacuumprecompressionmethodsofprocessareaProcessArea(m2)Averagedepthofsoftsoil(m)BearingCapacityoffoundationsoil(t/m2)Intervalofverticaldrains(m)Depthofverticaldrains(m)CalculatedFinalconsolida-tionsettlement(m)Depthofverticaldrains(m)CalculatedFinalconsolida-tionsettlement(m)EstimatedSettlement(m)Depthofverticaldrains(m)CalculatedFinalconsolida-tionsettlement(m)128254*__________2528614.4210.02.101.608.01.62.9510.02.301.808.01.90100.813.43.6010.02.692.408.02.35241428.00*____________37450.0013.3910.02.101.608.01.62.7210.02.301.808.01.90100.812.33.3010.02.692.408.02.15354313.00*____________49603.0013.0551.0212.02.5310.02.101.608.01.62.6510.02.301.808.01.90100.812.03.2310.02.692.408.02.15Note:The“*”showsthatthenumeratormeanstheproposedprocessarea,whichisextendedfromtheareaspecifiedinthetenderdocuments(denominator)byextendingedgeto4.0m.Whenf=7.5t/m2,thesettlement(1.8)iscalculatedbyusingtheaveragesettlementaftervacuumprecompressionofthemainbuildingofHiepPhoucpowerplant(1.55)addedsettlementoccurredinconsolidationperiod(90days)whichis(90*3)mm.GeotechnicaldesignofvacuumprecompressionmethodinprocessareaSchemeProcessArea(m2)Averagedepthofso