This paper investigated seismic performance of reinforced concrete (RC) single-column bridge bent with flexural failure under near-fault ground motion. Innovative nonlinear fiber-based finite element models (FEM) with combined damage mechanisms were proposed. Cracking and spalling of cover concrete, buckling of longitudinal reinforcing steel bars, and bond-slip effect were considered. To study bond-slip effect, two FEM were developed: model 1 (without bond-slip) and model 2 (with bond-slip). Nonlinear static cyclic pushover analyses and nonlinear response history analyses under scaled near-fault ground motion were conducted. The simulation results were compared with available pseudo-dynamic test results. Various ductility coefficients were evaluated to assess the seismic performance of RC bridge column. The attributes of near-fault ground motion on the seismic responses of RC bridge column were discussed. Model 1 overestimated the ultimate lateral load resistance, longitudinal reinforcing steel bar strain, and cover concrete strain. Model 1 also underestimated the lateral deflection of RC bridge column. The results of model 2 agree well with experimental observations including hysteretic responses and damage mechanisms. In general, the predictions of both models are in good agreement with the experimental observations. However, model 2 provides improved predictions on the seismic performance of RC single-column bridge bent under near-fault ground motion. It was also observed that maximum responses of RC bridge columns under near-fault motion were characterized by one or few large hysteretic cycles. The proposed models could also help practicing engineers and researchers simulate seismic performance of RC bridge columns under near-fault ground motions in a computationally efficient manner.

本文研究了近断层地震动下受弯破坏的钢筋混凝土（RC）单柱桥的抗震性能。提出了具有组合损伤机制的创新非线性基于纤维的有限元模型 (FEM)。考虑了保护层混凝土的开裂和剥落、纵向钢筋的屈曲和粘结滑移效应。为了研究粘滑效应，开发了两种 FEM：模型 1（无粘滑）和模型 2（有粘滑）。进行了缩放的近断层地震动下的非线性静态循环 Pushover 分析和非线性响应历史分析。仿真结果与可用的伪动态测试结果进行了比较。评估了各种延性系数以评估 RC 桥柱的抗震性能。讨论了近断层地震动对钢筋混凝土桥柱地震响应的影响。模型 1 高估了极限横向荷载阻力、纵向钢筋应变和保护层混凝土应变。模型 1 还低估了 RC 桥柱的横向挠度。模型 2 的结果与实验观察结果非常吻合，包括滞后响应和损坏机制。总的来说，两种模型的预测与实验观察结果非常吻合。然而，模型 2 对近断层地震动下弯曲的 RC 单柱桥的抗震性能提供了改进的预测。还观察到，RC 桥柱在近断层运动下的最大响应表现为一个或几个大的滞后循环。