填充墙对SRC-RC竖向混合框架结构抗震性能的影响

Effects of Infill Walls on Seismic Behaviors of the SRC-RC Vertical Hybrid Frame Structure

目的研究填充墙的布置对SRC-RC竖向混合框架结构抗震性能的影响,为结构设计提供参考.方法利用SAP2000对6种不同填充墙布置模型的静力弹塑性分析,即填充墙框架的Pushover曲线、承载力、延性、破坏机制以及性能点处的层间位移角.结果填充墙的不同布置改变了框架结构的刚度、内力分布和塑性铰破坏机制,填充墙满布以及底部无填充墙的层数小于转换层的SRC-RC竖向混合框架结构具有较好的抗震性能,其基底承载是无填充墙框架的2～5倍,延性系数降低,但在结构成为机构体系前,结构的塑性铰多且较为均匀,能够耗散罕遇地震释放的大量能量;转换层以上布置填充墙的结构基底承载力为无填充墙框架的1.2～1.5倍,在罕遇地震时塑性铰集中分布在底部无填充墙框架层,容易在转换层形成薄弱层.结论满布填充墙的SRC-RC竖向混合框架结构具有良好的抗震性能和抗倒塌性能;对于由于建筑需要底部无填充墙布置的SRC-RC竖向混合填充墙框架结构,底部无填充墙布置的层数宜小于转换层数.

This paper studied influences of different vertical layouts of infill walls on seismic behaviors of the SRC-RC vertical hybrid frame structure,so as to provide references for structural designs. Using softw are SAP2000,elastoplastic analysis on six layout types of infill walls to study the pushover curve,the bearing capacity,the ductility,the story drift angle and the failure mechanism of the structure was carried out. It is found that infill walls change the stiffness,redistribution of theinternal force and the failure mechanism of the frame. The SRC-RC vertical hybrid structure with uniform fully arranged infill walls and the same structure that the the number of story without infill walls is less than the the number of transfer layer,both have well seismic behaviors. Their horizontal bearing capacities are 2 ～ 5 times of that in the frame without infill walls. It is also observed that more uniformed distribution plastic hings appear in the vertical hybrid infill frame structure,which can absorb the earthquake energy before the structure is destroyed. The horizontal capacity of the frame with infill walls over the transfer layer is 1. 2 ～ 1. 5 times of that in the frame without infill walls. Under earthquake,the plastic hings intensively distribute on the bottom of the frame without infill walls,which easily cause weak layers in the transfer layer. Conclusion is that the SRC-RC vertical hybrid uniform arranged infill frame structure has well seismic behaviors and collapse capacities. For the SRC-RC structure,where the infill walls can not be arranged on the bottom,the number of the story without infill walls should be less than the number of the transfer story.