地震动群延时不确定性对反应谱的影响研究

为了考察外部激励群延时对反应谱的影响,分别从确定性的角度和统计的角度分析了群延时对线性单自由度结构体系位移响应最大值的影响。推导出了对应于给定单自由度结构体系在任意外部激励作用下最大位移响应的群延时。据此可以利用任意外部激励的群延时与结构体系的最大位移响应群延时的关系评估体系在该外部激励作用下位移响应峰值的大小。统计分析的结果表明:激励群延时的均值和方差对结构体系位移响应最大值的影响具有明显的规律性;激励群延时的分布频数与结构体系最大位移响应之间也存在着显著的关系。

Study on influence of earthquake GDT uncertainty on response spectra

In this paper,the influence of group delay time(GDT) of excitation on response spectra is investigated.The effect of GDT properties on the maximum displacement response of linear single-degree-of-freedom system is assessed by deterministic and statistical analysis.GDT corresponding to the maximum displacement response of a certain structure subjected to all kinds of excitations is derived.By checking the relationship between GDT of excitation and that of structure maximum displacement response,the peak displacement response of system under this excitation can be evaluated.Results of the statistical analysis show that there are significant relations between mean and variance of GDT of excitation and system peak displacement response as well as the frequency distribution of GDT of excitation and system peak displacement response.