基于IDA方法的高强钢组合Y型偏心支撑框架的结构影响系数研究

Study on structural behavior factor of high strength steel composite Y-type eccentrically braced frame based on incremental dynamic analysis

高强钢组合偏心支撑钢框架作为一种新型的抗震结构体系,我国抗震规范中未明确引入相应的结构影响系数.依据我国抗震规范设计了4个多高层高强钢组合Y型偏心支撑钢框架,采用增量动力分析(Incremental Dynamic Analysis)方法确定各算例的性能曲线,基于改进的能力谱方法确定了各算例的结构影响系数R和位移放大系数Cd.研究表明,高强钢组合Y型偏心支撑钢框架在设防烈度和罕遇烈度下变形均满足规范要求;结构影响系数可取R=4.889。

As a new anti-seismic structural system,the relevant structural behavior factor of high strength steel composite eccentrically braced frame,has not been introduced into current Chinese seismic code,4 multistory high strength steel composite Y-type eccentrically braced frames were designed on the basis of Chinese seismic code.The incremental dynamic analysis was carried out to get the global capacity spectrums of each model,and then the structural behavior factors R and the displacement amplification factors Cd were calculated by the improved capacity spectrum method.The seismic performance of the structures was studied.It was found that the structural deformation under moderate and rare earthquake can meet the requirements of Chinese codes.The value of the structure behavior factor is 4.889,and the value of the displacement amplification factor is Cd=6.693.It＇s conservative to design the new structural system based on the current Chinese codes.