斜向荷载作用下锈蚀RC矩形墩抗震性能拟静力试验及易损性分析

Quasi-static test and vulnerability analysis of seismic performance of corroded RC rectangular pier under oblique loading

为探究锈蚀钢筋混凝土(RC)桥墩在非正交水平荷载下的抗震性能,设计制作了4个不同加载角度构件进行拟静力实验,并利用OpenSees软件构建非线性有限元纤维模型,分析不同地震动入射角对其地震易损性的影响。结果发现:拟静力实验中,加载角度偏近弱轴,最大侧向力和屈服强度降低,达到最大侧向力的位移和屈服位移减小,极限强度降低,刚度和耗能能力下降,抗震性能减弱,但对位移延性系数影响较小;易损性分析发现:RC桥墩不同破坏状态对应的失效概率随PGA增大而增大。在PGA不变时,相同破坏状态下的失效概率随地震动入射角度由强轴趋向弱轴而增大。所做工作能为锈蚀RC桥墩的地震风险评估提供试验基础。

In order to explore the seismic performance of Corroded Reinforced Concrete(RC)piers under Non-Orthogonal Horizontal Load,four components with different loading angles were designed and manufactured to carry out Quasi-static test.After that,a Nonlinear Finite Element Fiber Model was established by OpenSees to analyze the influence of different loading angles of ground motion on its seismic vulnerability.The results show that,in the Quasi-static test,the more the loading angle is near the weak axis,the lower the maximum lateral force and yield strength,the lower the maximum lateral force and yield displacement,the lower the ultimate strength,the lower the stiffness and energy dissipation,and the lower the ASEISMIC performance,but it has little effect on the displacement ductility coefficient.The analysis of vulnerability shows that the failure probability of RC pier under different failure states increases with the increase of PGA.When PGA keeps constant,the failure probability of the same failure state increases as the loading angle of ground motion moves from major axis to minor axis.The work done here is able to provide experimental basis for seismic risk assessment of corroded RC piers.