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为了在城市复杂的交通工程中广泛应用部分填充混凝土钢桥墩,探明竖向偏心荷载作用下该类桥墩的抗震性能,以城市高架桥倒L形部分填充混凝土圆形钢桥墩为对象,采用试验与有限元分析方法,探究设计参数长细比、径厚比和竖向荷载偏心率对该类桥墩在顺桥方向力学性能的影响.首先,对以往4个竖向偏心荷载部分填充混凝土圆形钢桥墩柱试验试件进行有限元建模,通过有限元与试验结果对比分析,验证有限元模型单元选取、划分、接触和边界条件的合理性.然后,改变桥墩径厚比Rt、长细比λ及竖向荷载偏心率e/L,设计30个部分填充混凝土圆形钢桥墩进行非线性有限元分析.结果表明:在其他参数不变的情况下,随着λ从0.25增加到0.35,桥墩的最大承载力和延性均降低;随着Rt从0.06增加到0.12,桥墩的最大承载力缓慢增加,延性逐渐减小;随着e/L的增大,桥墩的最大承载力、延性均降低,抗震性能差;当e/L从0增加到0.2时,桥墩最大承载力、延性分别下降了约24％和50％;研究结果为部分填充混凝土钢桥墩在复杂荷载情况下的工程应用奠定了理论基础.“,”In order to widely apply partial concrete-filled steel bridge piers in the urban complicated traffic engineering,it was necessary to investigate the seismic performance of partial concrete-filled steel bridge pier with vertical eccentricity.The partial concrete-filled steel tubular bridge pier in inverse L-shape was taken to investigate the influence of design parameters including slenderness ratio,radius-thickness ratio and vertical load eccentricity ratio on the mechanical performance of such bridge piers along longitudinal direction through test and finite element analyses (FEA).First of all,finite element models of 4 partial concrete-filled steel tubular columns with vertical load eccentricity which had been tested previously were established.Through comparing values of FEA and experimental results,the rationality of selection,division,contact and boundary conditions of FE models was verified.Then,30 partial concretefilled steel tubular bridge piers were designed according to parameters of radius-thickness ratio Rt,slenderness ratio λ and vertical load eccentricity ratio e/L of bridge piers to conduct nonlinear FE analyses.The results show that in the case where other parameters is unchanged,when λ increases from 0.25 to 0.35,the bearing capacity and the ductility of bridge piers decreases.When Rt increases from 0.06 to 0.12,the bearing capacity increases and the ductility decreases.The bearing capacity and ductility of the bridge piers decreases with the increase of eccentricity ratio e/L,and seismic performance is poor.When e/L increases from 0 to 0.2,the bearing capacity and ductility of bridge piers decrease by about 24 ％ and 50 ％,respectively.The results of the research have provided the theoretical basis for engineering application on this kind of bridge piers under the complicated load condition.