冷弯薄壁型钢墙体恢复力模型及房屋地震反应简化分析方法研究

基于10片1∶1冷弯薄壁型钢墙体抗剪滞回性能试验结果,采用SAP2000中多线段塑性Pivot连接单元的滞回规则,进行墙体的恢复力模型及冷弯薄壁型钢房屋的动力非线性简化分析方法研究。研究表明:墙体的骨架曲线可采用退化四线型模型模拟;双柱墙体Pivot模型参数可取α=10、β=0.1,单柱墙体可取α=10、β=0.15;非线性简化分析与试验分析得到的滞回曲线的外包络线基本一致,耗能能力相当,简化方法能较好地模拟墙体的强度、刚度退化和捏缩效应;三层房屋结构简化计算模型的第1、第2阶振型与试验观测一致,频率分别相差11%和2%;模型结构与试验的地震反应分析结果吻合较好,表明简化计算方法可用于冷弯薄壁型钢房屋的弹性和弹塑性地震反应分析。

Study on restoring force model of cold-formed steel wall panels and simplified seismic response analysis method of residential buildings

Based on the test results of 10 full scale cold-formed wall panels under cyclic horizontal load,a restoring force model of cold-formed steel wall panels and nonlinear simplified seismic response analysis method for thin-walled residential buildings were studied by using the hysteresis rules of multi-linear plastic Pivot element in SAP2000.Results indicate that the skeleton curves of wall panels can be modeled by the degenerated quadruple-linear model;the Pivot model parameters α and β can be taken as 10 and 0.1 for double-column wall panels,10 and 0.15 for single-column ones,respectively;the envelope of hysteresis curves and capacity of dissipating energy of wall panels obtained from nonlinear simplified analysis are similar to those from test;the strength degenerated,stiffness degenerated and viscous phenomena of wall panels can be well modeled using the simplified analysis method;the first two modals of residential buildings obtained from the analysis is identical to those from test,and the difference of the fundamental and secondary frequency are 11% and 2%,respectively.Comparison of seismic analysis results show that the simplified analysis method can be applied to elastic and elasto-plastic seismic response analysis of thin-walled residential buildings.