带耗能腋撑型钢混凝土转换框架结构地震易损性分析

SEISMIC FRAGILITY ANALYSIS OF STEEL REINFORCED CONCRETE TRANSFER FRAME WITH ENERGY DISSIPATION HAUNCH BRACE

综合利用钢-混凝土组合结构技术和耗能减震技术,提出带耗能腋撑型钢混凝土新型转换结构,利用耗能腋撑改善转换结构抗震性能差的问题。以普通和带耗能腋撑型钢混凝土转换框架结构为研究对象,进行增量动力分析,建立该新型转换结构地震易损性曲线方程,研究防屈曲耗能腋撑对型钢混凝土转换结构破坏机制的影响。分析结果表明:防屈曲耗能腋撑有效降低型钢混凝土转换结构在中度、重度损伤破坏及倒塌破坏状态的超越概率,可作为一道可靠的抗震防线。耗能腋撑的设置避免了普通型钢混凝土转换框架结构在转换层及其相邻楼层处形成层侧移机构,减小转换构件的塑性变形,有效地防止型钢混凝土转换结构发生整体或局部倒塌破坏。

By utilizing a steel-concrete composite structure and energy dissipation technology,a kind of new transfer structure-a steel reinforced concrete（SRC） transfer structure with energy dissipation haunch brace（EDHB） was proposed to improve the seismic performances of transfer structures.The incremental dynamic analysis of SRC transfer frame without and with EDHBs was carried out and the seismic fragility curve equations of the new transfer structure were established.The influences of buckling-restrained EDHBs on failure mechanism of the SRC transfer frame were studied.The results show that the probability of exceedance of the SRC transfer frame in moderate,severe damage and collapse states can be significantly decreased by adding buckling-restrained EDHBs,and the EDHBs can become a reliable seismic fortification line.The lateral drift mechanism in the transfer story and neighboring stories of the SRC transfer frame can be avoided bybuckling-restrained EDHBs and the plastic deformation of transfer components can be alleviated.The global and local collapse of the SRC transfer frame can be prevented effectively by EDHBs.