强度折减因子是结构抗震设计中确定非弹性强度需求的主要依据,但是当前各国主要抗震国家仍然沿用传统的基于变形延性的强度折减因子,难以和新一代基于性能的抗震设计思想相融合.文中挑选四类场地下的强地震动记录,引入改进的Park-Ang双参数损伤性能评估模型,编程计算并分析了四类场地下基于性能的强度折减因子的分布特征,构造了5%阻尼比的基于性能的强度折减因子的回归模型,并给出了不同场地下的回归参数取值,可用于基于性能的结构抗震设计,并可供规范修编参考.
Strength reduction factor is the major basis for determining inelastic strength demand in seismic design of structures.However,at present the seismic codes of main countries are still using the traditional strength reduction factor based on deformation ductility,which is not consistent with the new generation’s performance-based seismic design philosophy.Strong ground motion records of four kinds of soil sites were selected,and based on the improved dual-parameter Park-Ang model for seismic damage performance evaluation of structures,the distribution characteristics of the performance-based strength reduction factor were analyzed by self-written program.The regression model of the performancebased strength reduction factor was extracted for 5% damping ratio,and the regression parameters under different soil sites were suggested,which could be used for performance-based seismic design of structures,and also as a reference for revision of related codes.