摘要
为研究有粘结预应力连接装配式桥墩的抗震性能,以通苏嘉甬铁路杭州湾跨海大桥引桥为背景,进行装配式桥墩和相应现浇墩大比例缩尺模型拟静力试验,研究装配式桥墩破坏模式、滞回特性、耗能、残余位移和曲率分布,并与现浇墩进行对比分析;采用OpenSees软件建立试验墩数值模型,对预应力轴压比、预应力筋初张力、预应力筋位置和恒载轴压比与预应力轴压比的比值进行参数敏感性分析。结果表明:有粘结预应力连接装配式桥墩破坏集中于墩台接缝处,主要表现为墩台接缝的张开闭合,墩身基本处于弹性状态;其承载力和延性均大于现浇墩,耗能和残余变形均小于现浇墩,曲率变化集中于墩台接缝处。预应力钢束采用分散边缘布置时,当恒载轴压比为0.1,为了避免混凝土过早被压碎,预应力轴压比不应超过0.3;改变预应力筋初张力,承载力基本没有变化,但会改变峰值荷载对应的位移;桥墩边缘布置预应力筋,有利于提高承载力,桥墩中心布置预应力筋,有利于减小残余位移;为了降低恒载P-Δ效应,恒载轴压比与预应力轴压比的比值不应大于1。
This study investigates the seismic performance of the segmental pier with bonded prestressed connections.With the Hangzhou Bay Sea-crossing Bridge carrying a section of the Nantong-Suzhou-Jiaxing-Ningbo High-speed Railway as a case,large-scale mockups of a segmental pier and a cast-in-place(CIP)pier were prepared for quasi-static tests.The mechanical properties of the segmental pier,including the failure mode,hysteresis characteristics,energy-dissipation capacity,residual displacement and curvature distribution,were analyzed and compared with those of the CIP pier.Both the segmental and CIP piers were numerically simulated in OpenSees,in which the sensitivity of parameters,including the axial compression ratio of prestress,initial tensions of prestressing tendons,locations of prestressing tendons,the axial compression ratio of dead load,and axial compression ratio of prestress,was examined.It is concluded that the damages of the segmental pier with bonded prestressed connections mainly appear in the joint of the pier and the abutment,being the opening and closing of the joint,and the pier is basically in elastic state.The load bearing capacity and ductility of the segmental pier are greater than the CIP pier,while the energy dissipation capacity and residual deformation smaller than CIP pier,and distinct curvature variation occurs in the joint of the abutment and the pier.When the prestressing tendons are arranged on edge of the pier and the axial compression ratio of dead loads is 0.1,the corresponding axial compression ratio of prestress should not be over 0.3,to avoid premature crushing of concrete.Changing the initial tension of prestressing tendons does not result in the fluctuation of the load bearing capacity of the pier,but changes the displacements associated with peak loads.Placing prestressing tendons on edge of pier can improve the load bearing capacity of the pier,and placing the prestressing tendons in the center of the pier is advantageous to the reduction of residual displacement.To reduce the P-Δeffect of dead loads,the ratio of dead loads and axial compression ratio of prestress should be less than 1.
作者
肖海珠
陈留剑
别业山
高立强
XIAO Haizhu;CHEN Liujian;BIE Yeshan;GAO Liqiang(China Railway Major Bridge Reconnaissance&Design Institute Co.,Ltd.,Wuhan 430056,China;State Key Laboratory of Bridge Intelligent and Green Construction,Wuhan 430034,China;China Railway Bridge Science Research Institute,Ltd.,Wuhan 430034,China)
出处
《桥梁建设》
北大核心
2025年第1期24-32,共9页
Bridge Construction
基金
湖北省交通运输厅科技项目(2020-186-2-8)
中国中铁股份有限公司科技开发计划项目(2019-重大-05,2021-专项-02)。
关键词
装配式桥墩
有粘结预应力
滞回特性
预应力轴压比
参数分析
拟静力试验
有限元法
segmental pier
bonded prestress
hysteresis characteristics
axial compression ratio of prestress
parametric analysis
quasi-static test
finite element method
