配置自复位耗能跨低多层钢框架体系的能量系数

Energy factors of low-to-medium-rise steel frame system equipped with self-centering energy dissipation bays

利用超弹性SMA螺栓梁柱节点的耗能能力和自复位特性,将其引入到耗能跨而构建“自复位耗能跨”,基于既有的节点试验研究结果对结构体系的滞回性能进行了探讨。在此基础上,以具有旗形滞回特征的单自由度体系为工具,对配置自复位耗能跨低多层钢框架体系的能量系数进行推导。能量系数可以合理量化具有旗形滞回规则结构的峰值响应需求,能量系数越低,表明地震动下结构的峰值响应越低。为了阐明滞回参数对能量系数的影响,对具有不同滞回参数组合可代表低多层结构的等效SDOF体系进行了非线性动力分析,参数组合包括周期、屈服后刚度比、延性系数及能量比。同时对能量系数的离散性也进行了分析。结果表明:能量系数及能量系数的离散性受结构周期、屈服后刚度比及延性系数影响较大,受能量比的影响较小。

In this paper,the energy dissipation capacity and self-centering characteristics of the super-elastic SMA bolted beam-column joints are applied in the energy dissipation bays to form a steel frame equipped with“self-centering energy dissipation bays”.The hysteretic behavior of the structural system was discussed based on the previous experimental work on a prototype connection.Utilizing the single-degree-of-freedom(SDOF)system assigned with the flag-shaped hysteretic characteristics,the energy factors of the low-to-medium rise steel frame system with self-centering energy dissipation bayswerederived.The energy factors can rationally quantify the peak response demand of the structure following the flag-shaped hysteretic law.The peak response of the structure under ground motions decreases with the reduction of the energy factors.In order to clarify the influence of hysteretic parameters on the energy factor,nonlinear spectral analyses wereperformed based on the equivalent SDOF systems of the low-to-medium-rise steel frame,and various combinations of the structural period,post-yielding stiffness ratio,ductility factor,and the energy ratio are included in the parameter matrix.The dispersion of the analysis results was presented.The analysis results indicate that the energy factors and the dispersion of the energy factors are appreciably influenced by the structural period,post-yielding stiffness ratio and ductility factor,and is less affected by the energy ratio.