考虑钢筋混凝土腐蚀效应的结构地震易损性分析

Seismic vulnerability analysis of reinforced concrete frame considering time effect

结构受周围环境的影响,在经历一定服役年限后,其力学材性的退化导致结构的抗震性能与刚度的退化,因而有必要在对结构进行性能评估与分析时,需要研究腐蚀效应的影响。结合已有的材性试验,总结了腐蚀效应对结构材料的力学特性的影响,并在考虑材料不确定性的基础上,利用拉丁超立方抽样方法建立结构与地震的随机样本,采用非线性时程方法与云图法对结构进行概率性分析。并以一座框架结构为例,建立了在不同服役年限下结构的地震需求与能力模型,并通过蒙特卡洛方法得到了地震易损性曲线。研究成果可为结构的全寿命设计、既有建筑结构的运营以及地震风险评估等提供理论依据。

With the increasing of the service time of structures,the materials may cause the degradation of seismic performance and stiffness. When encountering the earthquake,it should not guarantee that the structure completed its existing capacity in design period. By the existing experimental law and considering the structure randomness with Latin Cube sampling method,the vulnerability curves were obtained in different limit states by combining nonlinear time-history method and the probabilistic seismic demand model was built. Monte Carlo method was then applied to calculate the failure probability of structures. These achievements will provide theoretical basis and analysis support for the life-cycle design of RC frame,the operation and management,especially the seismic hazard assessment of existing structures.