北段二期沿海滩涂桩基施工控制要

'沿海滩涂桩基施工控制宋秀国二0一0年十二月summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 沿海滩涂桩基工程特点1.地质情况复杂：海相沉积层为主，年代近，淤泥、粉砂等薄弱层多，易造成塌孔。2.孔深、桩长：孔深80—105米，桩长80米左右，最长94米，停钻后泥浆沉淀快、厚，泥浆比重要求大。3.钢筋制作量大，连接难度大：钢筋数量多（一般每根桩55根主筋），钢筋直径大（Φ28螺纹钢）连接以机械连接为主，控制难度大，连接时间长，尤其是竖向连接。4.钢筋笼安放时间长：一般16小时左右，竖向连接难度大。5.砼灌注控制那难度大：时间长，压差变化大，易造成卡管、爆管，有问题时处理难度大。监理工作重点：1、水中及软基段桩基施工应注意护筒埋深（一般6-15米），确保稳定。2、从材料准备、设备配置（包括必要的备用设备）、人员配置、施工工艺各环节审查，清孔后尽快浇筑砼、确保砼连续进行，监理应密切配合，及时检查。3、钻孔前检查钻机固定情况，钻孔过程中应检查桩孔位置，防止偏孔。4、检查料斗容量和料斗高度，满足首批砼导管埋深大于2m和后期砼浇筑压力差的要求。5、逐节检查钢筋笼长度、钢筋直径和数量，钢筋笼下放后检查孔口安放位置，并采取措施防止砼浇筑时钢筋笼上浮。6、钢筋笼下放和水下灌注砼是重要的隐蔽工程，应加强检查及全过程旁站。7、督促做好钻孔、水下砼灌注等各项记录，确保数据准确、全面、确保数据真实。8、砼浇筑应按规范要求预留桩头长度，在桩检测前凿除。9、按要求的频率委托有资质的单位进行桩基检测。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 天津海滨大道沿海滩涂桩基施工控制一、工程概况海滨大道北段二期工程起自永定新河河口南侧的海滨大道疏港三线立交，向北先后跨越疏港四线和规划的永定新河主河道,沿线以高架桥的方式接海滨大道北段高速公路主线收费站。利用海滨大道北段高速公路与河北省沿海高速相接。本段路线全长9.12公里，其中桥梁长8.6公里，道路0.52公里，合同工期24个月，工程造价17.8个亿。本项目采用BT建设模式，监理费中标价1277万元，建设单位为天津一航海滨大道建设项目管理公司（业主单位：海滨大道建设发展有限公司），施工单位为中交一航局一公司和四公司。二、地质情况本工程大部分处于现状海挡以外的沿海滩地之中，区域气候为暖温带大陆性气候，季风显著，四季分明，春季干燥多风，夏季湿热多雨，秋季湿暖适中，冬季寒冷少雪。勘察最大钻孔深度120m，所揭示地层均属于第四纪全新统和更新统，按地质成因主要分为八个地质成因层，各土层时代成因及无力力学性质详细阐述如下：第Ⅰ海相层（Q42m）本层土为浅海相沉积，在本场地分布连续。根据工程性质可将本土层分为两个亚层：①-1层淤泥、淤泥质土：层厚1.00-10.00m，层底标高在1.44m-8.26m。①-2层粉土：层厚4.60m-18.00m。第Ⅱ陆相层（Q41al）summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 本层土为河流相沉积，在本场地分布连续，主要由粉质粘土组成。②层亚粘土：4.00-10.80m，层底标高在-19.43m-23.56m。第Ⅲ陆相层（Q3eal）本层土为河床-河漫滩相沉积，层厚6.00m-13.10m，层底标高在-29.28m～-33.29m。第Ⅱ海相层（Q3bm）本层土为滨海-潮汐带相沉积，在本场地分布连续，层厚10.30m-18.00m。第Ⅳ陆相层（Q3cal）本层土为河床-河漫滩相沉积，在本场地分布连续，层厚9.40m-17.00m，层底标高-55.94m~-60.08m。主要由粉细砂组成。第Ⅲ海相层（Q3bm）本层土为浅海~滨海相沉积，在本场地分布连续，本层土仅在ck2、ck3、ck4、ck5、ck5+、ck9、ck12、ck15、ck17、ck20、ck23、ck26、ck28、ck32、ck36、ck40、ck42号孔处揭穿，最大揭示厚度13.3m，在所揭示的深度内，主要由粉质粘土、粉细砂、粉土组成。第Ⅴ陆相层（Q3caal）本层土为河床~河漫滩相沉积，本层土仅在ck2、ck3、ck4、ck5、ck5+、ck12、ck17号孔处被揭穿，最大揭示厚度为17.00m，在所揭示的厚度内主要由粉质粘土、粉细砂组成。第Ⅳ海相层（Q23mc）本层土为滨海三角洲相沉积，在本场地内均为揭穿，最大揭示厚度为37.60m，在所揭示的深度内主要由粉质粘土、粉细砂组成。三、基础结构形式本工程桥梁工程采用钻孔灌注桩基础。特大桥8#、9#中墩桩径φ1.8m，8#墩桩长88m，9#墩桩长82m；7#、10#边墩桩径φ1.5m，7#墩桩长72msummerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- ，10#墩桩长68m。主线高架桥除特殊位置外，均采用单排桩接墩柱的布置形式，中墩桩径有φ1.5m，φ1.8m，φ2.0m三种桩径，桩长70～94m，且桩之间均有承台或系梁连接。四、桩基施工控制要点1、定位放线由于沿海滩涂地质不稳定，控制点易变动，所以控制点的选择至关重要，施工过程中还要经常复测。根据控制点进行桩基定位时最好应用GPS定位系统定位，钻具准备好开挖前再用钢尺现场量测检验，确保桩基定位无误。2、钻具的选择和泥浆制备本工程一开始选用的钻机有正循环钻机、反循环钻机、旋挖钻机三种。针对沿海滩涂的地质情况，通过试桩淘汰了反循环钻机，优先选用稳定性好的正循环大型回转钻、旋挖钻成孔，在钻进过程中合理控制钻进速度，确保泥浆护壁良好，泥浆池大小应能够满足钻孔需要，并设沉淀池进行掏渣，在钻进或清孔后及时检测泥浆各项指标是否满足规范要求，优质的泥浆能够减小孔内的沉淀厚度。特别注意旋挖钻成孔时要提前制备足够数量的合格泥浆，成孔后优先下放钢筋笼灌注砼，旋挖钻成孔的特点时速度快、沉淀少，缺点是容易产生缩颈或坍孔。3、护筒的选用根据大桥所处位置的地质情况，护筒的入泥深度特大桥不低于10米，其他墩位6-8米，采用导向架定位，震动锤打拔，顶标高同栈桥桥面标高或略高于平均高潮位，防止海水倒灌（护筒的制作标准及埋设位置偏差应满足设计和规范要求，又不能照搬规范，开始因为埋设4米护筒造成坍孔，护筒倾斜，险些造成事故）。施工过程中严格控制护筒内水头，避免因水头过低而引起坍孔，发现水头偏低时要及时补浆。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 护筒的拔除要在桩基混凝土灌注完毕后及时进行，当砼初凝后，护筒的拔除就变得相当困难了。由于护筒长度的加大，相应的刚度要求也要提高，制作要求工厂化，板材要求达到8-10毫米，现场拼装时对焊缝的要求高，避免在打拔过程中开裂。4、钻孔过程中的质量控制。对于正循环钻机钻孔时要采用悬吊法钻进，既钻头、钻杆的重量要靠钻机本身承重大部，控制钻进速度的目的是有利于孔壁的稳定，防止或减少坍孔的发生。因本桥位地层含有大量粉砂，需要足够大的泥浆池进行沉淀、滤出，在泥浆池布设受限的特大桥，通过试验在泥浆循环过程中串联小型离心机作为泥沙分离器，将泥浆中的砂分离出来，效果非常明显，二次清孔前的沉淀厚度从4-6米降到2-3米，甚至更低。另外，钻孔过程中泥浆比重控制在1.2-1.4之间，以提高泥浆的悬浮力和携带泥砂的能力。（钻进过程中常见的事故是钻头、钻杆等钻具的掉落，严重影响施工进度甚至造成重大经济损失，在钻具无法打捞的情况下还需进行设计变更）。5、二次清孔的控制指标。二次清孔泥浆比重：1.15-1.2，粘度：17-20s，含沙率小于：2%（钻孔过程中最好用泥沙分离器），严禁使用超钻代替二次清孔，沉渣厚度不大于15cm。6、钢筋笼的制作与安装的控制。受施工场地的影响，钢筋笼需要在加工场地分节制作完成后运至现场进行安装，在运输过程中要采取必要措施防止钢筋笼变形，在加强箍筋处增加“十字”支撑，在吊点处加木扁担，“十字”支撑在起吊安装后再行切除，钢筋笼变形后势必延长连接安放时间，增加孔内沉淀厚度，同时也增加了坍孔的机率，对桩基的质量构成潜在的威胁，应加强协调管理，从每一个环节入手缩短成孔到砼灌注之间的时间。海滨大道北段二期工程summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 钢筋连接有焊接和机械连接两种形式，其中机械连接中以直螺纹连接为主。由于本工程桩深、直径大，钢筋笼的连接接头多，下放时间较长，为节省钢筋笼的安放时间，降低坍孔机率，项目部对桩基钢筋笼主筋全部采用直罗纹连接工艺。下面主要介绍直螺纹连接方案和技术要求以及检验方法。为加强控制直螺纹连接钢筋的质量，必须对套丝进行严格的合格性检验，因此在钢筋套丝加工场地，施工单位必须配备专用的套丝质量检验工具环规、塞规（四件套）。直螺纹加工又分为剥离法和辊轧法，剥离法对钢筋原材的损伤比较大，辊扎法容易产生端头毛刺影响连接，综合比较我们选择辊扎法施工，施工过程中对毛刺及时进行打磨，辊扎刀具及时调整更换以满足技术规范的要求，要求施工单位对进场的原材料必须及时进行报验，对钢材必须按规范要求进行下垫上盖，对钢材成品、半成品，在运输时保证不变形，在使用前存放时场地要整平，下垫上盖，保证成品、半成品不变形、不锈蚀。（1）、施工前准备1）、设备调试a、根据所加工的钢筋规格、直径选用滚压轮型号；用调整试棒调整滚丝头内孔最小尺寸，然后更换相应规格的涨刀环，并调整好直径尺寸。b、调整挡块及滚压行程开关位置，保证滚压螺纹的长度。并检查限位器是否灵敏。c、打开润滑液开关，保证水流能够平稳流出（不能用油）。d、设备安装必须平稳，机床主轴轴心线应处于水平位置。2）、技术准备a、凡参与接头施工的操作工人，技术管理和质量管理人员，均应参加技术培训；操作工人应经考核合格后持证上岗。b、做好技术交底。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 3）、材料选择a、材料的品种规格，套筒的规格、型号以及钢筋的品种规格必须符合设计要求。b、操作人员须对每批进场钢筋，按不同规格进行施工前的接头连接检验（试连接），合格后方可在工程中进行施工。（2）、套筒检验1）、基本要求a、连接套筒宜选用45号优质碳素结构钢或其它经检验确认符合要求的钢材。供货单位应提供质量保证书，并应符合有关钢材的现行国家标准及JGJ107的有关规定。产品合格证应包括以下内容：型号、规格；适用钢筋的品种；连接接头的性能等级；产品批号；检验日期；质检合格签章；厂家名称、地址、电话；当有特殊要求时应表明相应的检验内容及指标。b、连接套筒尺寸应满足产品设计要求。套筒尺寸的允许偏差套筒外径D(mm)外径允许偏差(mm)壁厚(t)允许偏差(mm)长度允许偏差(mm)≤50±0.5＋0.12t－0.10t±2＞50±0.01D＋0.12t－0.10t±2c、连接套筒应按照产品设计图纸要求制造，重要尺寸(外径、长度)及螺纹牙型、精度应经检验。本工程连接套筒主要应用在Ⅱ32钢筋，经试验确定套筒长取7.8cm。d、钢筋连接套筒内螺纹尺寸宜按GB／T196确定；螺纹中径公差宜满足13B／T197中6H级精度规定的要求。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- e、连接套筒装箱前套筒应有保护端盖，套筒内不得混入杂物。f、连接套筒上应标明生产厂家标志。g、连接套筒的保护盖上应标志被连接钢筋的规格。h、连接套筒在运输过程中应妥善保护，避免雨淋、沾污或损伤。2）、质量要求a、外观质量：螺纹牙型应饱满，连接套筒表面不得有裂纹，表面及内螺纹不得有严重的锈蚀及其他肉眼可见的缺陷。套内无铁屑及杂物，连接套表面应有明显的规格标识。b、内螺纹尺寸的检验：用专用的螺纹塞规检验，其塞通规应能顺利旋入，塞止规旋入长度不得超过3P。螺纹检验示意图见附录c。3）、检验方法及频率a、连接套筒的外观质量检验应逐个进行。不合格的不准使用。b、连接套筒的内螺纹尺寸检验按连续生产的套筒每500个为一个检验批，每批按10％随机抽检，不足500个也按一个检验批计算。连接套筒的抽检合格率应不小于95％。当抽检合格率小于95％时，应另抽取同样数量的产品重新检验。当两次检验的总合格率不小于95％时，该批产品合格。若合格率仍小于95％，应对该批产品进行逐个检验，合格者方可使用。c、连接套筒质量检验要求序号检验项目量具名称检验要求1外观质量目测螺纹牙形饱满，表面无裂纹和影响接头质量的其它缺陷。2外型尺寸卡尺或专用量规长度及外径应满足尺寸公差要求3螺纹尺寸通端螺纹塞规能顺利旋入套筒并达到旋合长度止端螺纹塞规允许环规与端部螺纹部分旋合，旋入量不超过3p。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- d、检验完成后应填写连接套筒质量检验记录（见附表：1）（3）钢筋检验1)、进场钢筋必须有出厂质量证明书，进口钢材需有商检证明书，当运输，卸载，加工中有异常时要进行化学试验分析。2)、钢筋进场后按规范要求进行试验，当试验满足试验要求，并且得到监理工程师的认可后，方可进行钢筋的加工，不符合要求的钢筋不得进行直螺纹加工。3)、、钢筋下料要求：钢筋下料由其特殊性，若未按照要求下料将直接影响到后面的加工难度和质量4)、钢筋原材料强度必须满足设计及规范要求，钢筋直径偏差必须在允许范围内，如有过大的下偏差，会造成剥肋后直径偏小或不圆整，加工的丝头有秃牙、断牙现象，影响接头的强度。（4）丝头加工及检验丝头加工在项目部小临钢筋加工场，制作成半成品编号后分类堆存，根据现场需要，钢筋由汽车运输至现场。利用吊机吊运到场地进行连接。1）、丝头加工要求a、加工前，应保证钢筋端面平整并与钢筋轴线垂直；钢筋下料时不得用热加工方法切断；不得有马蹄形或扭曲；钢筋端部不得有弯曲；出现弯曲时应调直。b、丝头加工时应使用水性润滑液，不得使用油性润滑液。当温度低于0℃时，应掺入15％～20％亚硝酸钠，严禁使用油性润滑液或不加润滑液套丝。c、加工后丝头有效螺纹长度应满足设计规定。考虑工程的实际情况，丝头采用加锁母型（S）d、丝头中径、牙型角及丝头有效螺纹长度应符合设计规定。丝头螺纹尺寸宜按GB／T196确定；有效螺纹中径尺寸公差宜满足GB／Tsummerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 197中6f级精度规定的要求。e、丝头有效螺纹中径的圆柱度(每个螺纹的中径)误差不得超过0．20mm。f、标准型接头丝头有效螺纹长度应不小于l／2连接套筒长度，本工程丝头包括长、短两种，长丝头有效螺纹长度取8cm，短丝头有效螺纹长度取4.1cm。g、丝头加工完毕经检验合格后，应立即带上丝头保护帽或拧上连接套筒，防止装卸、搬运或者混凝土施工过程中污染、损怀丝头。根据钢筋直径选取不同大小的塑料保护套，保护套长度应比钢筋外螺纹长10～20mm，且保护套一端应封闭。h、在滚压过程中，每加工30个丝头要检查一次丝头尺寸及丝扣完成情况，发现偏差应及时调整滚丝机。不合格的丝头必须切掉重新加工。i、加工完成的丝头应按规格分类堆放整齐。2）、质量要求a、外观质量：丝头表面不得有影响接头性能的损坏及锈蚀。b、外形质量：丝头有效螺纹数量不得少于设计规定；牙顶宽度大于0.3P的不完整螺纹累计长度不得超过两个螺纹周长。c、丝头牙型检验：牙型饱满，无断牙、秃牙缺陷，且与牙型规的牙型吻合，牙齿表面光洁为合格品。3）、检验方法及频率a、丝头的尺寸及外观质量应符合要求。外观检查时，如发现有一个不合格，则该批接头应该逐个检查。b、丝头尺寸的检验：用专用的螺纹环规检验，其环通规应能顺利地旋入，环止规旋入长度不得超过3P。螺纹检验示意图见附录c。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- c、加工的丝头应逐个进行自检，不合格的丝头应切去重新加工。d、自检合格的丝头，应由现场质检员随机抽样进行检验。以一个工作班加工的丝头为一个检验批，随机抽检10％，且不少于10个。e、现场丝头的抽检合格率不应小于95％。当抽检合格率小于95％时，应另抽取同样数量的丝头重新检验。当两次检验的总合格率不小于95％时，该批产品合格。若合格率仍小于95％时，则应对全部丝头进行逐个检验，合格者方可使用。钢筋丝头的质量检验序号检验项目量具名称检验要求1螺纹牙形目测、卡尺牙形完整，螺纹大径低于中径的不完整丝扣累计长度不得超过两个螺纹周长2丝头长度卡尺或专用量规为标准套筒长度的1/2，其公差为＋2p（p为螺距）3螺纹直径通端螺纹环规能顺利旋入螺纹止端螺纹环规允许环规与端部螺纹部分施合，旋入量不应超过3Psummerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- f、检验完成后应填写现场钢筋丝头加工质量检验记录表（见附表：2）（5）连接前检验钢筋连接施工之前，应对每批进场钢筋进行接头工艺检验。每种规格钢筋的接头试件不得少于3根，钢筋母材抗拉强度试件不应少于3根，且应取自接头试件的同一根钢筋。接头试件的抗拉强度应符合Ⅰ、Ⅱ级接头的要求。钢筋连接前，钢筋丝纹和连接套筒丝纹要逐个进行检查，确保其完好无损，如果发现丝纹表面有杂质，应清除干净。（6）钢筋连接及检验1）、钢筋连接施工a、主筋连接镦粗直螺纹连接必须满足施工技术规范要求，钢筋主筋接长施工应满足，同一断面接头的截面面积不超过总截面面积的50%，且相邻接头断面间距大于35d。b、钢筋的表面应洁净，使用前应将表面油渍、漆皮、鳞锈等清除干净。c、钢筋骨架的高度必须严格控制，在认真复核图纸、精准推算顶板保护层尺寸后，进行反算控制骨架主筋、高度。d、钢筋连接前要按钢筋布间距在钢筋上作出标记，严格按标记布设、绑扎钢筋。e、骨架成型截面尺寸确保准确，不允许偏大，防止模板安装发生困难，钢筋的的间距、型号必须与设计一致。f、在进行钢筋连接时，钢筋规格应与连接套筒规格一致，并保证丝头和连接套筒内螺纹干净、完好无损。g、套筒连钢筋时，应先对正一端钢筋中线旋入另一侧钢筋，用手拧至不动时，采用扳手或管钳对套筒进行旋拧。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 安装时，首先把连接套筒的一端安装在基本钢筋的端头上，用扳手或管钳等工具将其拧紧到位，然后把导向对中钳夹紧连接套筒，将待接钢筋通过导向夹钳中孔对中，拧入连接套筒内拧紧到位，即可完成连接。卸下工具后随即检验，不合格的立即纠正，合格的接头作上标记，与未拧紧的接头区分开来，以防有的钢筋接头漏拧，并认真做好现场记录工作。h、钢筋连接时应用工作扳手将丝头在套筒中央位置顶紧。i、钢筋丝头保护帽应在钢筋连接前拧入套筒时逐一取下，不应集中取下多个保护帽。j、钢筋接头拧紧后应用力矩扳手按不小于下表中的拧紧力矩值检查，并加以标记。滚轧直螺纹钢筋接头拧紧力矩值钢筋直径≤1618～2022～2528～3236～40拧紧力矩值/（N·m）80160230300360注：当不同直径的钢筋连接时，拧紧力矩值按较小直径钢筋的相应值取用。k、力矩扳手的精度为±5％，要求每半年用扭力仪检测一次。2）、质量要求a、钢筋连接完毕后，连接套筒外应有外露有效螺纹，且连接套简单边外露有效螺纹短丝头不得超过2P，长丝头不得超过4cm。b钢筋连接完毕后，拧紧力矩值应符合要求，严禁对连接处进行点焊。3）、检验方法及频率a、钢筋连接接头的外观质量及拧紧力矩应符合要求。b、钢筋连接接头的外观质量在施工时应逐个自检，不符合要求的钢筋连接接头应及时调整或采取其他有效的连接措施。c、summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 外观质量自检合格的钢筋连接接头，应由现场质检员随机抽样进行检验。同一施工条件下采用同一材料的同等级同型式同规格接头，以连续生产的500个为一个检验批进行检验和验收，不足500个的也按一个检验批计算。d、对每一检验批的钢筋连接接头，于正在施工的工程结构中随机抽取15％。且不少于75个接头，检验其外观质量及拧紧力矩。e、现场钢筋连接接头的抽检合格率不应小于95％。当抽检合格率小于95％时，应另抽取同样数量的接头重新检验。当两次检验的总合格率不小于95％时，该批接头合格。若合格率仍小于95％时，则应对全部接头进行逐个检验。在检验出的不合格接头中，抽取3根接头进行抗拉强度检验，3根接头抗拉强度试验的结果全部符合．JGJ107的有关规定时，该批接头外观质量可以验收。f、检验完成后应填写现场钢筋接头连接质量检验记录表（见附表：3）钢筋接头外观及拧紧力矩检验步骤summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- （7）、试验控制1）、钢筋连接接头的现场拉伸试验，应符合JGJ107的有关规定。2）、用于直接承受动力荷载结构中受力钢筋的连接接头，应根据JGJ107中有关疲劳性能检验的规定。3）、钢筋连接接头力学性能检验a、现场施工前，应按．IGJ107的规定进行接头工艺检验。滚轧直螺纹钢筋连接技术的提供单位应向使用单位提交有效的型式检验报告。b、钢筋连接接头的现场检验按检验批进行。同一施工条件下采用同一材料的同等级同型式同规格接头，以连续生产的500个为一个检验批进行检验和验收，不足500个的也按一个检验批计算。c、summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 对每一检验批接头，应于正在施工的工程结构中随机截取试件，并按JGJ107的有关规定检验。d、钢筋连接接头单向拉伸试验的结果应符合．JGJ107的有关规定。e、在现场连续检验10个检验批，当其全部单向拉伸试件均一次抽样合格时，检验批接头数量可扩大为1000个。f、在钢筋连接接头进行检验前，应对钢筋母材进行力学性能检验。试验方法应符合GB／T228的有关规定。检验结果应符合GB1499或GB13014的有关规定。（8）、其它注意事项1)、螺纹加工应随工程进度随制随用，不宜过早的加工好。因为钢筋在轧制过程中裸露的新鲜表面极易被锈蚀，影响连接质量，造成施工困难。2)、雨季或长期码放情况下，应对丝头采取防锈措施。丝头在运输过程中应妥善保护，避免雨淋、沾污、遭受机械损伤。3)、控制连接质量的3个要点：a套筒两端处外露的钢筋丝扣圈数不能太多，也不能一点螺扣也不外露。如果一点也不外露，就不能保证钢筋两端互相顶紧贴合。b控制套筒和钢筋加工精度，及时用通规和塞规检验，如精度不够及时调整机械。c旋合时，保证达到规定的拧紧力矩值。只要达到规定的力矩值，使螺纹之间的配合间隙消除，即可满足接头强度和变形的要求。summerofmasonryconstruction,brickrequiressufficientmoist.8.6.2.6youmusttakethefollowingmeasurestoconcreteconstructioninsummerhightemperatureimpactonconcretea.hardeningspeedup,vibratingdifficultiesreducedbleeding,fastdrying,easytocrack(plastic),highearlystrength,fastearlyhydrationheat,lesscooling,temperatureincreasesrapidly,duetotemperaturedifferencecracks.B.pouringdaytimehightemperatures,duetothehightemperatureeffectofconcretestrength,stability,invaryingdegrees,onmixingprocesses,perfusionvibrationandmoistureconservation,effectivemeasuresshouldbetaken.2)mainmeasurestakenbya.temperaturecontrolthewatertemperatureinyourstandardmixproportionofconcrete2degrees,theconcretetemperature0.5degrees.B.withthecontrolledadditionofretarderagentcanreducetheeffectsofconcreteunderhightemperature,butmakesomeperformancedegradationofconcrete,sowhenyouareusingadditivesmustbeimplementeduponapprovalbythesupervisingengineer.C.timecontrolsuitableforworkatnight,shouldseektoreducethemixingtimeandshippingtimeathightemperatures.D.strengthentheconservationandhightemperaturesafterpouringintheearlydaysofcontinuouswaterconservationtopreventsurfacedryingandcoveringthin-filmwetgrassbagtomakeitmoistStatein24hours.8.6.38.6.3.1winterconstructionmeasuresinwinterconstructionpreparation1)requiredwinterconstructionmaterials,equipment,planningaheadoftimecomesinto-17- 附表：1连接套筒质量检验记录承包单位：监理单位：工程名称套筒规格抽检数量拟用部位生产日期代表数量生产单位外观检验：（套筒外观检验时，应该对所有套筒进行检验。检验完成后，对其外观进行整体的描述，对有外观缺陷的套筒，应注明数量、缺陷情况及处理方法。）螺纹尺寸检验序号套筒直径套筒螺纹检验套筒外观情况备注通塞规止塞规质检员（监理员）：日期：注：本表格施工、监理单位按照要求的检测频率分别进行检查填写。1 附表：2现场钢筋丝头加工质量检验记录表施工单位：监理单位：工程名称钢筋规格抽检数量工程部位生产班次代表数量提供单位生产日期接头类型检验结果序号钢筋直径丝头螺纹检验丝头外观检验备注环通规环止规有效螺纹长度不完整螺纹外观检查质检员（监理员）：日期：5 附表：3现场钢筋接头连接质量检验记录表施工单位：监理单位：工程名称钢筋规格抽检数量工程部位生产班次代表数量提供单位生产日期接头类型检验结果序号钢筋直径扭紧力矩检验值外露有效螺纹检验备注上下质检员（监理员）：日期：5 6、混凝土生产质量的控制。和易性和坍落度必须符合设计要求：1）混凝土等级c35。2）标号：P.042.5R。3）坍落度：18-22cm。4）导管埋置深度：2-6m。5)混凝土含气量：4.5%-6%。6）灌注时间不大于砼初凝时间。7)超灌高度不小于1m。要求项目部要切实按规范、设计及总监办的相关要求对混凝土质量严格把关，做到不符合要求的混凝土不出厂，到场后不符合要求的不入模。在施工中，首灌砼入模前，必须先检测砼拌合物性能及含气量（掺引气剂），且每工作班不得少于4次，当对混凝土有疑问或监理要求时必须进行检测。8、砼灌注的控制。为保证特大桥桩基的完好率，砼灌注用导管在首次使用前必须进行水密性试验，磨损严重或有缺陷的导管不得使用，封底砼数量、导管悬空高度必须满足规范要求，砼要选用优质高性能混凝土，严格控制坍落度、含气量等各项指标，严格控制导管的埋深在2-6米5 之间，加强对设备、工具的检查，选用熟练的工人进行操作，避免因人为操作造成砼卡管、掉导管等事故的发生。加强对施工便道的疏导，优先放行砼运输车，确保砼供应及时，砼灌注结束前施工技术员应及时核对砼用量，砼灌注高度应大于桩顶标高1米以保证桩顶砼质量。同时，桩基净保护层厚度必须满足7.5cm的设计要求。灌注过程中的质量事故主要有：砼卡管无法继续灌注；导管爆裂泥浆倒灌造成断桩；导管坠落事故；风暴潮造成海水倒灌泥沙淤积造成事故桩等。针对不同情况分别采取相应得处理措施，将损失降到最低，其中砼灌注过程中的导管二次插入法在其他项目中没有应用，其操作时机掌握不好适得其反，本项目通过对二次插管灌注桩的取芯检测，验证了其满足要求。在没有相关操作经验和断桩部位较深时最好不要采用此方法。9、成桩符合检测要求的全部进行超声波检测和实体强度检测，如有异常或疑问采取钻芯取样验证，事实证明通过声测报告反映完整性不合格的桩基，通过取芯样检查相应部位砼离析情况，这种双重检测相互验证避免了质量隐患和重大损失，在以后的工程中值得推广。5 5'