预制桥墩节段节点抗剪性能有限元模拟及参数分析  

Finite-element simulation and parametric analysis of shear resistant performance of precast concrete segment column joints

作　　者：奚康[1] 吴威业 布占宇[1] XI Kang;WU Wei-ye;BU Zhan-yu(Faculty of Architectural,Civil Engineering and Environment,Ningbo University,Ningbo 315211,China)

机构地区：[1]宁波大学建筑工程与环境学院,浙江宁波315211

出　　处：《宁波大学学报（理工版）》2018年第5期67-72,共6页Journal of Ningbo University：Natural Science and Engineering Edition

基　　金：国家重点研发计划(2017YFC0702900);浙江省基础公益研究计划工业项目(LGG18E080004)

摘　　要：鉴于预制节段拼装混凝土桥墩中存在节段-节段接缝,而接缝(节点)属于受力薄弱环节,由此对预制拼装桥墩节段节点的抗剪性能进行研究,设计制作了一组桥墩节段节点抗剪试件进行拟静力加载试验,并建立三维有限元分析模型,通过与试验结果的比较,验证了有限元模拟方法的正确性.然后利用有限元模型进行了另外2组节段节点抗剪模型加载模拟,得到了各试件在不同约束应力作用下的剪切力—剪切位移关系曲线以及剪力键在不同受力阶段的开裂形态等结果.在比较了有限元分析得到的节点抗剪承载力与AASHTO规范的计算结果后,发现AASHTO规范公式低估了平接缝与实心截面多剪力键干接缝的抗剪承载力;同时在高约束应力下,应适当减小AASHTO规范公式中的摩擦系数,才能与试验结果一致.Precast segmental concrete bridge piers（PSCBP） have segment-segment joints.The concrete is not continuous at these joints,which are weak links under load effect.To study shear performance of PSCBP joints,a group of pier segment joint shear test specimens were designed and fabricated.Then quasi-static test was conducted on the specimens.The three-dimensional finite element model of tested specimen was elaborated and the finite element simulation（FES） was validated through the comparison with the experimental results.Then the loading simulation on two additional joint shear models was carried out with the preceding FE model.The analysis results,such as the shear stress-shear displacement curve and the cracking patterns of shear keys at different loading stages,were derived.Finally the joint shear capacity by FES and that per AASHTO specification were compared.The results show that the AASHTO specification equation underestimated the shear capacity of solid section multiple keyed dry joints and flat dry joints.And when at high confining pressure,the friction coefficient in the AASHTO formula should be reduced in order to make the calculation results to be consistent with the test results.

关 键 词：桥墩节段 预制施工 干接缝 有限元模拟 抗剪承载力 

分 类 号：U443.22[建筑科学—桥梁与隧道工程]