泄洪洞进水塔预应力闸墩承载特性研究.docxVIP

泄洪洞进水塔预应力闸墩承载特性研究凯1伍鹤皋1冲1周立本2雄2苏李张(1.武汉大学水资源与水电工程科学国家重点实验室,武汉430072;2.中国水电顾问集团中南勘测设计研究院,长沙410014)摘要:预应力锚固技术是改善大型弧门结构应力状态、优化闸墩结构的重要工程措施之一.针对某泄洪洞进水塔,建立了三维数值模型,采用有限元法进行了计算分析;以施工期和运行期闸墩混凝土应力状态为控制标准,进行了预应力方案的比选,并进行了锚索张力、弧门水推力和库水压力等荷载的敏感性分析.计算结果表明:随着拉锚系数的增加,预应力区混凝土的压应力数值增加,上游预留平孔位置和下游支撑结构位置的应力集中程度也增加;在预留平孔附近位置主要受锚索张力影响,是应力集中区域,需要配置环形受拉钢筋;在预留平孔下游部位,弧门水推力和边墙外库水压力造成的拉应力区可以通过锚索张力产生预压应力得到有效地降低或消除;而预留平孔上游部位出现的较大拉应力,则由弧门水推力、锚索张力和边墙外水压力共同作用形成,需要加大边墙厚度或配置受拉钢筋.关键词:泄洪洞;进水塔;闸墩;预应力锚固技术;拉锚系数;有限元中图分类号:TV662.2文献标识码:A文章编号(2008)0220006206StudyonLoadBearingCharacteristicsofPrestressedPierinSpillwayTunnelSuKai1WuHegao1LiChong1ZhouLiben2ZhangXiong2(1.StateKeyLaboratoryofWaterResourcesandHydropowerEngineeringScience,WuhanUniv.,Wuhan430072,China;2.Mid2southInvestigation,DesignResearchInstitute,ChineseHydroelectricEngineeringConsultantCompany,Changsha410014,China)AbstractPrestressedanchortechnologyisoneofthemainmeasurestoimprovethestressesstatusinlargeradialgateandtooptimizethepierstructure.Accordingtoanintaketowerinspillwaytunnel,a32DmodelisbuiltandFEMisadopted.Theoptimizationofprestressschemeisdonebythestressesstatusinpierconcreteduringtheconstructionstageandoperationperiod.Andtheinfluenceofanchortension,hydraulicthrustonradialgateandtheoutsidewaterloadisanalyzed.Someconclusioncanbedrawnfromtheresultsasfollows.Aspull2anchorcoefficientincreasing,thecompressionstressinconcretebecomeslarger,andstressconcentra2tionlevelnearthepreparedholeandthebolsterbecomeshigher.Thereisastressconcentrationzoneneartheupstreampreparedholeandannulartensionreinforcementisrequired.Thetensionstresszoneinthedown2streamofpreparedhole,whichiscausedbyhydraulicthrustonradialgateandtheoutsidewaterload,canbereducedbytheanchortension.Thetensionstresszoneintheupstreamofpreparedholeisthecommonresultofhydraulicthrust,outsidewaterloadandanchortension;andthesidewallisrequiredtobethickerandten2sionreinforcementisalsorequired.pull2anchorcoeffi2Keywordsspillwaytunnel;intaketower;pier;prestressedanchortechnology;cient;FEM收稿日