中文摘要：

为了阐明弯曲和扭转耦合作用下RC圆形桥墩的抗震性能,对扭弯比不同的12个RC圆形桥墩进行了循环试验研究,并基于试件的破坏特征、滞回性能和钢筋应变等试验观测结果,分析了弯扭复合作用下扭转作用对桥墩抗弯能力的影响,以及配筋率、箍筋间距及箍筋形式对桥墩弯曲和扭转性能的影响;采用有限元软件ABAQUS模拟了不同扭弯比的RC圆形桥墩在弯扭复合作用下的破坏特性和弯扭承载能力。研究结果表明：弯扭相互作用降低了RC圆形桥墩的抗弯和抗扭承载力,桥墩的变形特征和失效模式发生了改变,损伤破坏区要高于弯曲塑性铰长度区域,提出的＂交叉互锁＂螺旋箍筋形式可有效解决由于扭转效应导致的RC圆形桥墩承载能力降低的问题。

英文摘要：

To investigate the seismic performance of RC circular bridge columns subjected to combined bending and torsional loadings, cyclic testings on twelve specimen columns were performed under combined bending and torsion loadings. Based on the observed and measured damage characteristics, hysteresis behaviors and rebar strains of tested specimens, the effect of torsion loading on bending resistance and the effects of reinforcement ratio, reinforcement space and its form on the bending and torsion behaviors of RC bridge columns were analyzed. The damage characteristics and bending and torsion capacities of specimen columns were simulated by using ABAQUS software. The results show that the bending and torsion capacity is decreased due to the effect of bending-torsion interaction, the failure modes and deformation characteristics are changed and the damage zone tends to move upwards from the typical bending plastic hinge zone. A novel cross interlock spiral reinforcement type is presented which can effectively improve the bearing capacities of RC bridge columns under combined bending and torsion loadings.