翼墙-框架结构振动台试验研究及有限元分析

Shaking table test and finite element analysis of wing wall-frame structure

为研究翼墙-框架结构在地震作用下的抗震性能和加固效果,进行了一个缩尺比为1∶4的翼墙-框架结构模型振动台试验,得到了结构在烈度为7度的多遇、设防和罕遇地震以及8度、9度地震动作用下的动力特性、动力反应和宏观破坏模式。研究表明:翼墙根部首先受到往复拉压破坏,框架柱得到有效保护,实现了多道抗震防线的目的;梁端出现大量裂缝,基本实现了"强柱弱梁"屈服机制,而纯框架数值模型则呈现典型的柱铰破坏机制;纯框架模型的底层层间位移角显著大于上部各楼层,翼墙-框架模型各楼层的层间位移角大小基本一致,层屈服机制得到有效避免。

Shaking table test of a 1∶ 4 scaled wing wall-frame model was conducted to study the seismic behavior and strengthening effect of this structural system. The dynamic characteristics,seismic responses and failure mechanism of the test model under a series of excitations with gradually increasing acceleration amplitudes are presented in this paper. The research shows that wing walls damage first due to repeated tension and compression so that columns are protected effectively,indicating multiple seismic fortification levels. A large amount of cracks occur at the end of beams,the ‘strong column-weak'beam mechanism is basically realized. On the contrary,column hinges mechanism happens in the numerical model of an ordinary RC frame. The inter-story drift ratio of the bottom story is obviously larger than that of the upper stories in the ordinary RC frame,while the value of inter-story drift ratio is basically the same among the stories in the wing wall-frame. The story yield mechanism is avoided.