极低屈服点软钢阻尼器恢复力模型的研究

Study on hysteresis loops of dampers made of ultra low yield point steel

本文通过试验和理论分析探讨极低屈服点软钢阻尼器的恢复力特性。随着塑性变形的发展将恢复力模型中的骨架曲线进行平移,其卸载曲线用Ramberg Osgood函数来描述,由此得到的恢复力模型定义为骨架平移模型,将其应用于描述极低屈服点软钢阻尼器的恢复力特性。为了验证该模型的有效性并确定合理的参数,对安装极低屈服点软钢阻尼器的3层钢框架结构进行了拟动力试验,同时用该骨架平移模型模拟极低屈服点软钢阻尼器的恢复力特性进行了大量的弹塑性地震反应分析。通过取用不同平移系数时的数值计算结果与拟动力试验结果的比较,发现平移系数为0.6左右时,该模型具有较高的精度。

An experimental and theoretical study of the hysteresis loops of dampers made of ultra low-yield-point steel is presented in this paper. When the plastic deformation is developing, skeleton curves are moved and the unloading paths of the curves are described with Ramberg-Osgood function. The obtained hysteresis model is defined as skeleton shift model and applied to the dampers made of ultra low-yield-point steel. In order to verify the accuracy of this model and confirm proper parameter, the pseudo-dynamic tests and a great deal of inelastic earthquake response analysis are carried out on a scaled 3-story steel frame that attached with hysteresis dampers. The results of numerical analysis using the different shift ratio are compared with the results of pseudo-dynamic test. It is found that the accuracy of this model is satisfying when the shift ratio equals 0.6.