罕遇地震下的屈曲约束支撑框架结构的动力响应研究

为分析支撑布置方式、刚度比、结构总层数等因素在罕遇地震下对屈曲约束支撑框架结构动力响应的影响,借助有限元分析软件SAP2000,分别对6层、12层、18层屈曲约束支撑框架结构模型进行了罕遇地震下的时程分析,详细研究了多高层结构体系的层间位移角、底层剪力、支撑内力等随支撑布置方式、刚度比、结构总层数等因素变化的规律。分析表明,倒V较单斜布置更能有效降低底层剪力、增大支撑轴力、降低层间位移角,从而降低结构的地震响应,更有利于结构消能减震;随着结构总层数的增大,支撑的屈服层数呈现出增多的趋势;刚度比七为2—4时,能使较多层数的屈曲约束支撑参与到消能减震的过程之中,较好地实现抗震设防目标。

Study on Dynamic Response of Buckling Restrained Braced Frame Structures under Rare Earthquake

To analyse the influence of the buckling restrained brace (BRB) arrangement, the lateral stiffness ratio, the total layers on the buckling restrained brace frame structures (BRBF) dynamic response under rare earthquake, we conducted the time-history analysis of six stories, twelve stories and eighteen stories buckling restrained braced frame structures under rare earthquake. In this paper, the inter-layer displacement angle, the bottom layer shear and the brace force with the buckling restrained brace arrangement, the lateral stiffness ratio and the total layers changing were studied. Our results showed that the bottom layer shear and the inter-layer displacement angle was reduced, the brace force was increased effectively with the V inverted arrangement than single oblique arrangement. The BRB yield layers increased with the increase of total layers. The seismic goal was achieved better when the lateral stiffness ratio were between 2 and 4.