安庆长江铁路大桥主墩深水钢围堰拆除技术.pdf

《安庆长江铁路大桥主墩深水钢围堰拆除技术.pdf》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。

1、桥梁建设２０１６年第４６卷第５期（总第２４０期）BridgeConstruction，Vol．４６，No．５，２０１６（TotallyNo．２４０）１文章编号：１００３－４７２２（２０１６）０５－０００１－０５安庆长江铁路大桥主墩深水钢围堰拆除技术农代培（中铁大桥局集团有限公司，湖北武汉４３００５３）摘要：安庆长江铁路大桥主桥为主跨５８０m的连续钢桁梁斜拉桥，该桥３号、４号桥塔墩基础采用双壁钢围堰施工，钢围堰外径５６m、壁厚２m，总高分别为４２．８８m和４１．４m。为满足通航净空要求，承台面以上钢围堰需全部拆除。主桥完工后，在枯水期，沿承台面拆除钢围堰，

2、拆除高度２２．３８m，在高度上分２节、平面上分１６块拆除，按自下游向上游方向进行拆除。钢围堰拆除时，先在围堰内开设切割通道，然后按先竖缝、后水平缝的顺序切割，最后切割隔舱板和顶部连接处。水面以上钢围堰均采用常规氧气法切割；水面以下围堰内无沉积物时，直接采用水下氧－弧切割法切割钢围堰；由于３号墩钢围堰内有较多沉积物，先抽水，割开围堰内壁板，将围堰内沉积物凿除后，再灌水，进行水下切割。关键词：高速铁路桥；斜拉桥；钢围堰；拆除；水下切割；凿除；桥梁施工中图分类号：U４４３．１６２；U４４８．２７文献标志码：ATechniquesforDemolishingof

3、DeepwaterSteelCofferdamsofMainPiersofAnqingChangjiangRiverRailwayBridgeNONGDaipei‐（ChinaRailwayMajorBridgeEngineeringGroupCo．，Ltd．，Wuhan４３００５０，China）Abstract：ThemainbridgeofAnqingChangjiangRiverRailwayBridgeisacontinuoussteeltrussgirdercable‐stayedbridgewithamainspanof５８０m．Thefou

4、ndationsforthepylonpiersNo．３andNo．４ofthebridgewereconstructed，usingthedouble‐wallsteelcofferdamsthathadtheexternaldiametersof５６m，wallthicknessof２mandtotalheightrespectivelyof４２．８８mand４１．４m．Toaccordwiththenavigationalclearancerequirements，thepartsofthecofferdamsabovethepilecaptops

5、shouldbecompletelydemolishedafterthemainbridgewasconstructed．Inthedemol‐ishingconstruction，thecofferdamsweredemolishedalongthepilecaptopsinthelowwaterperiodandthedemolishingheightofthecofferdamswas２２．３８m．Intheheight，thedemolishedpartofacofferdamwasdividedinto２tiersandintheplan，wa

6、sdividedinto１６segmentsandthedemolis‐hingwascarriedoutfromthedownstreamsidetotheupstreamsideoftheriver．Whenthecoffer‐damswerebeingdemolished，thecuttingaccesseswerefirstlyopenedupinthecofferdams，thecuttingthenproceededinthesequenceofcuttingtheverticaljointsfirstandthehorizontaljoin

7、tslateandfinallythebulkheadsandtheconnectionsatthetopsofthecofferdamswerecut．Thepartsofthecofferdamsabovethewaterwerecut，usingthecommonoxygencuttingmethodandforthepartsofthecofferdamswithnosedimentbelowthewater，thepartswerecut，directlyusingtheunderwateroxygen‐arccuttingmethod．Sin

8、cetheconsiderableamountofthesedimentexis