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为了给预制拼装桥墩抗震设计计算提供参考,针对典型预制拼装桥墩所采用的仅无黏结预应力或无黏结预应力+耗能钢筋连接方式,考虑混凝土、耗能钢筋和预应力筋的非线性本构模型,推导了预制节段拼装桥墩多节点转动推覆分析计算过程.基于关键截面弯矩-曲率分析确定弯矩承载力和对应的墩顶水平荷载,然后计算各个接缝的弯矩和曲率,进而计算墩顶位移.开展了2种接缝连接方式预制节段拼装桥墩试件拟静力试验,将多节点转动推覆分析方法模拟结果与拟静力试验结果进行对比,分析预制拼装桥墩水平抗力-侧移曲线以及接缝张开、预应力筋应力、墩柱转角随侧移的变化,各种位移机理对墩顶位移的贡献,接缝处混凝土应变等.研究结果表明:多节点转动模型与单节点转动模型水平承载力计算结果基本一致,而多节点转动模型桥墩侧移计算结果大于单节点模型计算结果,多节点模型计算精度更高;多节点转动模型接缝张开、预应力筋应力和接缝转动计算结果与试验结果基本一致;开始时墩顶位移主要由剪切位移和整体弯曲位移提供,随着墩顶位移的增大,墩底接缝转动对墩顶位移的贡献逐渐占主导地位;墩柱混凝土轴向应变测试结果验证了各个接缝处混凝土应变随着墩高逐渐降低的趋势,接缝处的混凝土轴向应变远大于墩柱混凝土轴向应变.“,”To provide reference for the seismic calculation of precast segmental bridge columns (PSBC),in the light of two connection manners with unbounded prestressing tendon or prestressing tendon plus energy dissipation (ED) bar employed in typical PSBCs,the multi-joint rotation analytical pushover (MRAP) calculation process of PSBC was deduced,considering the nonlinear constitutive model of concrete,ED bar and prestressing tendon,respectively.The flexural moment capacity and the corresponding column tip lateral force were determined based on critical section moment-curvature analysis.Then the flexural moment and curvature on every joint were derived,whilst the column tip displacement was calculated.Two quasi-static tests of PSBC with two kinds of joint connections were conducted.The MRAP simulation results were compared with quasi-static test results.The lateral resistant force-drift curve,joint opening,prestressing tendon stress,and column rotation variation with drift,the contribution of every mechanism to column tip displacement,and the concrete strain near the joint were analyzed.The results show the lateral resistant force calculation results by MRAP method are nearly the same with those by single-joint rotation method.But the displacement calculation results in view of MRAP are larger than those by single-joint rotation method.The calculation precision of MRAP is better than that of single-joint rotation method.The calculation results of joint opening,prestressing tendon stress,and joint rotation by MRAP is consistent with test results.The column tip displacement is mainly provided by shear displacement and global flexural displacement at the beginning.Subsequently,with the increasing of column tip displacement,the contribution of column base joint rotation is dominant.The tendency of concrete strain at joint gradually decreases with the increasing of height is validated by test results of column concrete axial strain.The concrete strain on joints is much larger than that of column axial strain.