填充墙对框架结构抗震性能的影响

Study on influence of infilled walls on seismic performance of RC frame structures

框架填充墙结构在汶川地震中产生了严重的震害,我国现行抗震设计对填充墙的考虑难以保证结构在地震下的抗震性能,研究一套简单有效考虑填充墙在地震中不利影响的设计方法是亟需解决的问题。本文按规范设计框架结构算例分别进行弹性、静力弹塑性和非线性动力分析,考察填充墙在弹性和非线性阶段对框架结构的刚度、内力和变形的影响,特别是在强震中的不利影响;从中寻找弹性设计与非线性反应之间的关系而提出弹性设计中考虑填充墙不利影响的方法。结果表明,均匀满布填充墙对框架结构抗震总体上是有利的;填充墙平、立面不均匀布置对框架结构抗震不利;填充墙约束效应易产生附加剪力和短柱破坏。最后根据分析结果提出设计、管理中考虑填充墙影响的方法和措施。

InfiIled frames had enormous damage in Wenchuan Earthquake. It is not always safe to have the effect of the infilled walls. It is most necessary to develop the method to consider the effect of the infilled walls on the frames when making the seismic design of the frames. Based on the elastic analysis, static nonlinear analysis and dynamic nonlinear analysis of the frame structures, which are designed according to the current Chinese seismic codes, the effects on the internal force, stiffness and deformation in the frames caused by the infilled wall, especially in the strong earthquake, are achieved and then the measures to consider the adverse effect of infilled wall are taken. The conclusions are as follows ： it is unfavorable to the frame when the infilled walls are not evenly distributed. It is easy to present the additional shear and the short columns damage caused by the local restraint effect of infilled wall. In the end, this paper proposes the measures to consider the infilled wall in the seismic design and management.