多遇地震下填充墙侧向刚度对RC框架结构抗震性能的影响

目前,我国RC框架结构抗震设计通常采用纯框架模型:将填充墙作为非结构构件,不考虑其抗侧力作用仅将墙体重量当作外荷载加到计算模型上,通过减小结构自振周期考虑填充墙对结构整体刚度增大作用。然而,多遇地震下填充墙具有一定的抗侧刚度,在其影响下纯框架计算模型是否合理有待商榷。针对该问题,建立考虑填充墙布置的RC框架结构计算模型,并进行线性动力时程分析。对计算结果进行分析表明:当填充墙均匀布置时,从框架部分承担水平地震作用力方面考虑纯框架模型是合理的,而从框架柱轴压力方面考虑又是不合理的;当填充墙不均匀布置时,结构抗震性能的各个指标均有很大的不同,纯框架模型是不合理的。

The influence of infill wall lateral stiffness on the seismic performance of RC frame structures under small earthquakes

Now,seismic design of RC frame structures in China use usually pure framework model.In the model,infill walls are considered as non-structural components,namely their lateral force does not considered,only the weight of walls as the external loads are added to the calculation model,and the structural vibration period appropriate is reduced to consider the role of overall the structure stiffness increased by wall filled.However,under small earthquake,infill walls have a certain degree of resistant lateral stiffness.In this paper,in order to discuss the justifiability of this method,linear dynamic time-history analysis of RC frame structures,considering the layout of the infill walls,are analyzed.The results show that: when infill walls uniform layout,from horizontal seismic forces of frameworks bearing angle,pure framework model is reasonable,but from pressure the frame column axis angle is unreasonable;when infill walls non-uniform layout,the pure framework model is unreasonable.