装配式T梁负弯矩索加固方法及锚梁优化研究  

Research on Reinforcement Method of Continuous Fabricated T-beam with Negative Moment Cable and Optimization ofAnchor Beam

作　　者：刘汉彪 胡建华 刘海波 LIU Hanbiao;HU Jianhua;LIU Haibo(Hunan Provincial Communication Planning,Survey and Design Institute,Changsha,Hunan 410219,China;Hunan Communications&Water Conservancy Group Ltd.,Changsha,Hunan 410008,China)

机构地区：[1]湖南省交通规划勘察设计院有限公司,湖南长沙410219 [2]湖南省交通水利建设集团有限公司,湖南长沙410008

出　　处：《公路工程》2021年第3期239-243,283,共6页Highway Engineering

基　　金：湖南省科技重大专项(2017SK1010)。

摘　　要：装配式连续T梁结构在设计施工过程中由于设计平纵线形指标低、施工管控不到位或作业条件差等原因,致使墩顶的负弯矩预应力张拉不达标甚至失效,这将对桥梁结构的安全性与耐久性造成严重风险。针对装配式T梁负弯矩区域失效的问题,以碾子冲大桥为工程背景,提出了一种采用钢锚梁对拉体外预应力钢束的加固方法,并对锚梁进行了优化分析。结果表明:根据缺补相等原则,采用钢锚梁对拉体外索加固方案,有效地解决了负弯矩索失效问题;体外索锚固产生的桥面板板顶横向最大拉应力为1.14 MPa,板底横向最大拉应力为0.83 MPa;分析表明下翼缘主拉应力是钢锚梁设计的主控因素。In the process of design and construction of fabricated continuous T-beam structure,due to the low horizontal and vertical alignment index,construction control is not in place or the operation conditions are poor,the negative bending moment pre-stress tension of pier top is not up to standard or even invalid,which will cause serious risk to the safety and durability of the bridge structure.Therefore,in view of the failure of the negative bending moment area of the fabricated T-beam,this paper takes Nianzichong Bridge as an example for the engineering background,an innovative reinforcement method using steel anchor beam to tension external pre-stressed steel bundle is proposed,and the optimization analysis of the anchor beam is carried out.The results show that:according to the principle of equal deficiency and compensation,the reinforcement scheme of steel anchor beam with opposite external cables is convenient and effective to solve the problem of negative moment cable failure;the maximum transverse tensile stress at the top of the deck slab is 1.14 MPa,and the transverse maximum tensile stress at the bottom of the slab is 0.83 MPa;the optimization analysis shows that the main tensile stress of the lower flange is the main control factor in the design of the steel anchor beam.

关 键 词：负弯矩索 钢锚梁 体外索加固 优化设计 分析 

分 类 号：U445.72[建筑科学—桥梁与隧道工程]