随机地震动输入模型研究及渡槽抗震分析

Random Ground Motion Input Models and Seismic Analysis of Aqueduct Structure

在平稳地震动过程的Kanai-Tajimi模型和Clough-Penzien模型的基础上,分别建立了2种全非平稳地震动加速度过程的广义演变谱模型。根据我国现行的《水工建筑物抗震设计规范》(DL 5073—2000),确定了2种广义演变谱模型的参数值。应用非平稳随机过程模拟的谱表示-随机函数方法,分别生成了基于2种广义演变谱的全非平稳地震动代表性时程集合,并进行了二阶数值统计值的对比分析。同时,通过代表性时程集合的平均反应谱与规范反应谱的拟合比较,发现K-T(Kanai-Tajimi)广义演变谱模型更适用于水工建筑物抗震设计。最后,将K-T广义演变谱模型与概率密度演化理论相结合,对渡槽结构进行了随机地震反应和抗震可靠度分析。

On the basis of the Kanai-Tajimi model and Clough-Penzien model of stationary ground motion processes,two types of generalized evolutionary spectral models of fully non-stationary ground motion acceleration process are established,respectively. According to the Code for seismic design of hydraulic structures（ DL 5073—2000）,the parameter values of generalized evolutionary spectral models are identified. Applying the spectral representation and random function method,the representative samples ensemble of fully non-stationary ground motion process for the two generalized evolutionary spectral models are generated,and the comparative analysis of the second-order numerical statistics is carried out. Moreover,through comparing the average response spectrum of representative samples ensemble and response spectrum calculated by the code,it is found that the generalized evolutionary spectral models of Kanai-Tajimi spectrum is more applicable to seismic design of hydraulic structure. Finally,through combining Kanai-Tajimi generalized evolutionary spectral model with probability density evolution method,the random seismic response analysis and reliability evaluation of an aqueduct structure is investigated.