罕遇地震下自定心支撑张弦桁架振动响应分析

针对带自定心耗能支撑张弦桁架在罕遇地震作用下的振动响应,将自定心耗能支撑与大跨张弦桁架结构相结合,利用有限元软件建立单榀带自定心耗能支撑张弦桁架的分析模型,采用弹塑性时程分析研究结构在罕遇地震激励下主桁架结构屈服时的振动响应。分析结果表明,自定心耗能支撑能够改善结构的振动特性,可有效减小结构震后残余变形。研究了自定心耗能支撑的启动力、启动位移和强度比等关键滞回参数对结构振动响应的影响,结果表明:增大支撑启动力可以有效控制水平方向的残余变形;减小支撑强度比可以增强自复位能力,但会降低支撑自身耗能能力;启动位移对结构峰值位移有一定影响,对残余变形影响较小,但当启动位移过大时,支撑的自复位能力会有所降低。

Study on Seismic Response of Cable-Supported Truss with Self-Centering Energy Dissipation Brace

This paper introduces self-centering energy dissipation brace into the cable-supported truss, and for the cable-supported truss with self-centering energy dissipation brace. This paper studies the seismic response of cable-supported truss combining the self-centering energy dissipation brace. First, the finite element model is constituted. Then, the inelastic time-history analysis method is used to analyze the vibration response under strong seismic excitation. The result shows that self-centering energy dissipation brace effectively improves the vibration performance and reduces the residual deformation. In addition, the parametric analysis is conducted to analyze the influence of the activation force, activation displacement and strength ratio on the vibration performance. Analytical results indicate that increasing the activation force can effectively control the residual deformation in horizontal direction; diminution of the brace strength ratio improves the self-centering performance, but reduces the energy dissipation capacity of brace; activation displacement has certain influence on peak displacement and minor effect on residual displacement; however, self-centering capacity declines with large activation displacement.