DDC灰土挤密桩施工方案

在高压缸排汽的总管上装有动力控制止回阀，以便在事故情况下切断，防止蒸汽返回到汽轮机，引起汽轮机超速。在高压缸排汽总管的端头有蒸汽冲洗接口，以供在管道安装完毕后进行冲洗，在管道冲洗完成后用堵头堵死。centerpinchecksandanchoringtheinnercylinder.AccordingtoWhilecouplingalignmentshouldkeepoiloutofcavityandlocatetherotoraxisneckraisedarewithintheprescribedlimits,thereshouldbenogaps,Horn,HornandHorn0.05mmfeelergaugesfitinto.Centercoupling,condenserwaterfillingandwater-filledaccordingtofactoryrequirement.ForcouplingthreesupportedrotorCenter,themouthunderthecouplingbetweenthevalueshouldbeasstipulatedinthemanufacturer,usually0.15~0.25mm.Inthecaseofcouplingconnection,ifpossible,liftingonlyonebearingendofthesupportbearingoftherotor,removethebearing,fittedwithspecialtilesandspecialliftingtools,discrotors,checkthejournalfluttertile,shouldgenerallybelessthan0.10MM.Whenthecouplingsandrotorcomeswhenthereisaconflict,thecouplingCentreshallprevail.6.4.5.2.2shaftlookingfor:...6.4.5.3.Provisionalboltconfirmedthepositioningoftherotorsize,aswellasthecouplingbetweentheadjustmentshimthicknessaccuracy,drawingstomeetthetechnicalrequirements.Plane,cylindricalandcleanthecouplingboltholesshouldbecleanandwithoutburrs,scrapironandgrease-free,relativepositionofthecouplingaccordingtothedrawingrequirementsare.Couplingtopscrews,rounddistanceapart,indicatorstomonitormovementoftheaircraft,itsvalueisallowedtopassthevalueaxismoving,mountedadjustmentpads,notepadsinstallationdirectionguidepincouplingwithprocessendclosed.Thebackwheelsslowlytightened,when2mmorso,withstandardwhitebarswheretwobackwheelboltholemeasurementaboveandbelow,confirmtwobackwheelboltholeconcentricity.Then,thesymmetricalhorizontalmounttwotemporaryboltstightened,attentiontomonitordialindicator,theninstallthesymmetricaltemporarybolts,thistimesitesslowlymovingrotor,inthemeasuredcircumferenceof8equalpartsbackwheelrimrock,eachmeasuringrelativechangesinvalueshouldbelessthan0.02mm.6.4.5.4couplingreamedandpairedboltreamingdiereamer,adjustablereamers,boringmill,inseveralways.6.4.5.4.1Generalrequirementsbeforereamingorboring,一、工程概况及设计要求：本工程为西安科技大学体育训练中心灰土挤密桩地基处理工程，位于雁塔路与南二环十字。场地地形平坦，建筑场地为湿陷性黄土场地，湿陷等级为Ⅱ级。灰土挤密桩桩径不小于400mm，扩桩至600mm，桩长4800mm，桩间距900mm，排距780mm，总根数3721根。采用2：8灰土挤密桩复合地基。要求处理后的复合地基承载力特征值≥220KPa。桩长范围内，桩间土湿陷性全部消除；桩孔内用2：8灰土分层回填夯实，桩体内的平均压实系数不小于0.97，桩间土的平均挤密系数不小于0.93，最小值不小于0.90。二、方案确立：工程桩在96.64M-91.84M之见土中，地勘报告显示此处土层为湿陷性黄土土层，湿陷等级为Ⅱ级，土质不均匀，结构杂乱，孔隙发育，结构松散，中部土具有中等湿陷性属中偏高压缩性土，下部土具有中等~强烈湿陷性；均具有自重湿陷性，持力黄土层属高压缩性土层。根据设计的桩间土挤密系数要求及地基承载力要求，依据检测部门前两次试桩提供的数据及现场土质情况及地勘报告16页-7.1条复合地基方案建议现采用孔内深层强夯法（DDC工法）施工。三、施工准备：a)施工前，项目部组织有关技术人员熟悉图纸图纸并对每个桩进行编号，做到一一对应，了解设计意图，掌握施工重点和施工规范，安排人员、设备进场，测量定位等各项工作。在高压缸排汽的总管上装有动力控制止回阀，以便在事故情况下切断，防止蒸汽返回到汽轮机，引起汽轮机超速。在高压缸排汽总管的端头有蒸汽冲洗接口，以供在管道安装完毕后进行冲洗，在管道冲洗完成后用堵头堵死。centerpinchecksandanchoringtheinnercylinder.AccordingtoWhilecouplingalignmentshouldkeepoiloutofcavityandlocatetherotoraxisneckraisedarewithintheprescribedlimits,thereshouldbenogaps,Horn,HornandHorn0.05mmfeelergaugesfitinto.Centercoupling,condenserwaterfillingandwater-filledaccordingtofactoryrequirement.ForcouplingthreesupportedrotorCenter,themouthunderthecouplingbetweenthevalueshouldbeasstipulatedinthemanufacturer,usually0.15~0.25mm.Inthecaseofcouplingconnection,ifpossible,liftingonlyonebearingendofthesupportbearingoftherotor,removethebearing,fittedwithspecialtilesandspecialliftingtools,discrotors,checkthejournalfluttertile,shouldgenerallybelessthan0.10MM.Whenthecouplingsandrotorcomeswhenthereisaconflict,thecouplingCentreshallprevail.6.4.5.2.2shaftlookingfor:...6.4.5.3.Provisionalboltconfirmedthepositioningoftherotorsize,aswellasthecouplingbetweentheadjustmentshimthicknessaccuracy,drawingstomeetthetechnicalrequirements.Plane,cylindricalandcleanthecouplingboltholesshouldbecleanandwithoutburrs,scrapironandgrease-free,relativepositionofthecouplingaccordingtothedrawingrequirementsare.Couplingtopscrews,rounddistanceapart,indicatorstomonitormovementoftheaircraft,itsvalueisallowedtopassthevalueaxismoving,mountedadjustmentpads,notepadsinstallationdirectionguidepincouplingwithprocessendclosed.Thebackwheelsslowlytightened,when2mmorso,withstandardwhitebarswheretwobackwheelboltholemeasurementaboveandbelow,confirmtwobackwheelboltholeconcentricity.Then,thesymmetricalhorizontalmounttwotemporaryboltstightened,attentiontomonitordialindicator,theninstallthesymmetricaltemporarybolts,thistimesitesslowlymovingrotor,inthemeasuredcircumferenceof8equalpartsbackwheelrimrock,eachmeasuringrelativechangesinvalueshouldbelessthan0.02mm.6.4.5.4couplingreamedandpairedboltreamingdiereamer,adjustablereamers,boringmill,inseveralways.6.4.5.4.1Generalrequirementsbeforereamingorboring,2b)机具设备：①成孔设备：履带式桩机一台，DD30柴油桩锤、桩管各一套；②夯扩设备：1.5t细长重锤及自行式夯机4台；③灰土拌和及运输设备：40装载机一台，0.8装载机一台；④主要工具：电焊机一台，配电箱两个，三相电缆500米，铁锨、架子车若干。四、施工方案：1.施工顺序：根据《建筑地基处理规范》(JGJ79-2002.14.3章节）有关规定及技术要求，灰土挤密桩施工顺序为采用先里排后外排，隔排隔桩跳打法施工。2.工艺流程：场地平整放线定桩位桩机就位成孔夯填检验3.放线定桩位：根据控制轴线，将排桩控制线引至基坑周边，然后根据施工图纸放出桩中心位置，用木楔或白灰点（用钢钎打入土中20～30cm拔出后用白灰灌孔）做好标记，桩位偏差控制在0.4D（D=桩孔直径）以内。测量员应及时复核，准确无误后方可根据所放桩点成孔。为了保证放线的准确性，应尽量安排在白天进行，以免夜间放线错误，发现在高压缸排汽的总管上装有动力控制止回阀，以便在事故情况下切断，防止蒸汽返回到汽轮机，引起汽轮机超速。在高压缸排汽总管的端头有蒸汽冲洗接口，以供在管道安装完毕后进行冲洗，在管