武汉青山长江公路大桥19号主墩钻孔桩施工技术.pdf

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1、桥梁建设２０１６年第４６卷第３期（总第２３８期）６BridgeConstruction，Vol．４６，No．３，２０１６（TotallyNo．２３８）文章编号：１００３－４７２２（２０１６）０３－０００６－０５武汉青山长江公路大桥19号主墩钻孔桩施工技术吏林山（中铁大桥局集团有限公司，湖北武汉４３００５０）摘要：青山长江公路大桥主桥为（３５０＋９３８＋３５０）m双塔双索面斜拉桥，１９号主墩采用６０根变直径钻孔桩基础，桩长９２m（上部２５m为３．０m，下部６７m矱为２．５m）。综合考虑矱地形、水文、地质、工期等多方面因素，１９号主墩钻孔桩施工采用“吹填

2、筑岛＋旋挖钻机”方案。吹填筑岛平台（平面尺寸为１１８m×７１m）作为钻孔施工平台，将水上施工转变为陆上作业，吹填筑岛平台形成平台后，采用５００t履带吊机辅以免共振电动振动锤插打钢护筒；钻孔桩采用大型旋挖钻机钻进成孔，辅以优质泥浆配备及循环系统，采用气举反循环工艺进行清孔；钻孔桩清孔后，下放钢筋笼（长９３．７m，采用胎架长线、少节头法制作），钢筋笼下放后，采用导管法灌注C４０水下混凝土，完成钻孔桩施工。１９号主墩钻孔桩施工后，经超声检测，桩身均为Ⅰ类。关键词：斜拉桥；钻孔桩；吹填筑岛平台；钢护筒；旋挖钻；双层钢筋笼；桥梁施工中图分类号：U４４８．２７；

3、U４４５．５５６文献标志码：AConstructionTechniquesforBoredPilesofMainPierNo．19ofQingshanChangjiangRiverHighwayBridgeinWuhanLILinshan‐（ChinaRailwayMajorBridgeEngineeringGroupCo．，Ltd．，Wuhan４３００５０，China）Abstract：ThemainbridgeoftheQingshanChangjiangRiverHighwayBridgeinWuhanisacable‐stayedbridge

4、withdoublepylons，doublecableplanesandwithspanarrangement（３５０＋９３８＋３５０）m．ThefoundationforthemainpierNo．１９ofthebridgeistheonethatiscomprisedof６０nos．ofthevariablediameterboredpiles（thediametersoftheupper２５mofthepilesbeing３．０mwhilethoseofthelower６７mbeing２．５m）andthelengthofthepilesis

5、９２m．Incomprehensiveconsiderationofthevariousfactorsofthetopography，hydrology，geologyandconstructiontimescheduleinconnectionwiththeconstructionofthepiles，itwasdeterminedthatthepilesshouldbeconstructed，usingtheschemeofthe“hydraulicreclamationislandplatform＋rotaryboringma‐chine”．T

6、hereclamationislandplatform（theplandimensionsoftheplatformbeing１１８m×７１m）wasusedastheboringconstructionplatformandtheconstructionovertheriverwasthustrans‐formedtothatontheland．Afterthereclamationislandplatformwaswellconstructed，thesteelcasingsforthepileswereinsertedanddriven，usi

7、ngtheresonance‐freeelectricalvibrationhammeraidedbythe５００tcaterpillarcrane．Theholesofthepileswereboredbythelargerotaryboringmachine，thehigh‐qualityslurryandcirculatingsystemwereprovidedintheboringandtheboredholeswereclearedbytheair‐liftingreversecirculation．Whentheholeswereclea

8、redoff，therein‐forcementcages（acagebeing９３．７mlongandbe