地震波持时效应能量评价指标研究

Energy evaluation indicator for ground motion wave duration effects on SDOF systems

将结构地震损伤定义为结构在单向振动过程中耗储地震能量能力的降低,据损伤成因将结构地震损伤分离为残余位移损伤与退化损伤,并据结构退化损伤量值界定地震波持时效应大小。将结构总输入能、能量增长持时、最大瞬时输入能量比及90%能量持时作为持时指标,通过56条地震波三种周期SDOF结构损伤分析,讨论各持时指标与结构退化损伤间的相关度。分析结果表明结构总输入能与结构退化损伤间的相关度最高。由于总输入能求解受结构阻尼模型与滞回模型影响较小,将总输入能作为地震波持时效应评价指标具有较好的准确性与便利性。

A new seismic damage model of SDOF systems was developed based on variation of strain energy dissipation capability in a push-over process. The seismic damage index was divided into a residual displacement index and a degradation damage index according to causes damage of damage. Effect of ground motion wave duration on a SDOF system was quantified as a degradation damage index. Based on the damage analysis of three SDOF structures with different natural periods using 56 ground motion waves, the correcation levels between 4 evaluation indicators （input energy, duration of input energy, ratio of maximum transient input energy to input energy and 90% relative energy duration） and the degradation damage index were investigated. The results showed that the input energy affected indistinctively by damping models and hysteretic models is the most correlated one with the degradation damage index of SDOF systems; therefore, the input energy is a nice evaluation indicator for ground motion wave duration effects on SDOF systems.