冷弯薄壁型钢组合墙体非线性滑移滞回模型研究

为了研究冷弯薄壁型钢组合墙体的滞回性能,对4 片3m×2.4m(高×宽)不同构造的冷弯薄壁型钢组合墙体足尺试件进行了拟静力试验。根据试验所得的滞回规律,采用Richard-Abbott 曲线,建立了能反映其滞回曲线非线性、滑移捏缩、强度和刚度退化特征的三段式非线性滑移滞回模型,并在Origin8.0软件里辨识了各试件模型中的待定参数。研究结果表明:影响滞回曲线的主要因素为墙体先前经历的最大位移;典型捏缩滞回环的上升或下降段曲线可分为刚度单调变化的三段;用参数辨识结果得到的仿真滞回曲线与试验滞回曲线吻合较好,三段式非线性滑移滞回模型能较全面地反映冷弯薄壁型钢结构组合墙体的滞回特征、模型表达式直观、各参数物理意义明确且易于识别。

RESEARCH ON NONLINEAR PINCHING HYSTERESIS MODEL OF SHEATHED COLD-FORMED THIN-WALLED STEEL STUD WALLS

In order to study the hysteresis performance of sheathed cold-formed thin-walled steel stud walls,four full-scale 3m×2.4m(height by width) specimens,with different configurations,were tested under cyclic loading.According to the hysteresis rule achieved from experiments,the three-segment nonlinear pinching hysteresis model,capable of representing specimens’ hystersis charactersitcs of nonlinear,pinching,strength and stiffness deteroiration,is established by using Richard-Abbott curve.And model parameters of specimens were estimated by Origin 8.0 software.The experimenal investigation indicates that the experienced maximum displacement is the key factor that influenes the hysteresis curve,and the ascending or descending curve of typical pinching hysteresis loop can be divided into three segments,where each one has monotone stiffness change.The hysteresis curves,simulated by the three-segment nonlinear pinching hysteresis model,agree well with experimental hysteresis curves,showing the proposed model can represent the stud walls’ hysteretsis behavior comprehensively.Moreover,with intuitive mathematical expression,parameters of the model have clear physical meanings and they are easy to estimate.