加设翼墙RC框架结构抗倒塌试验研究

Experimental Study on the Collapse of Multi-Story RC Frame Structure

汶川地震中的极震区域内,钢筋混凝土框架结构出现了严重的整体倒塌型破坏,造成难以承受的人员伤亡和财产损失。本文从框架结构抗震设计概念和实际震害出发,针对框架结构在地震中出现强梁弱柱型层屈服机制提出研究方向,通过分析带翼墙框架结构的实际震害和振动台模型试验肯定此类结构的极震抗倒塌能力。振动台试验主要以北川老县城一栋抗震性能良好的底框结构为原型,选取1∶4缩尺比例设计带翼墙的框架结构实验室模型,进行振动台试验。试验现象表明,加设翼墙后结构塑性铰出现在底层柱底和各层梁端,结构出现"强柱弱梁"的整体屈服机制,通过分析模型在试验中的地震响应得到带翼墙的框架结构可承受0.58W的水平荷载,对应1/50的整体位移角,表明加设翼墙后的框架结构具有良好的极震抗倒塌能力和可靠的冗余度。

Based on the seismic design concept and actual seismic damage,this thesis has made profound research on the ＂strongbeam-weak-column ＂ response which leads column sides way mechanism. By analyzing the seismic performance of shear-wallstrengthened frame structures and the response of shaking table tests,the excellent collapse-resistent capacity of such structures is confirmed. A bottom frame structure,which is exhibited excellent seismic performance during the sever earthquake in Beichuan County,is taken as an example,a RC frame model with wing-wall strengthened is designed and built with appropriate scaling factor to explore the collapse-resistent capacity in shaking table test. The analysis shows that the model has sustained numerous horizontal loads as large as fifty-eight percents of total weight and story drift reaching 1 /50. All these indicate the preeminent collapse-resistent capacity and substantial redundancy of the model.