多年冻土区场地地震动随机特性研究

Study on stochastic earthquake characteristics of ground in permafrost regions

利用随机振动理论和动力分析的有限元方法,对青藏铁路多年冻土区场地进行了随机地震反应分析,分析了多年冻土区场地随机地震特性,研究了冻土层厚度的变化对场地随机地震特性的影响,获得了场地卓越频率及地震响应峰值。研究结果表明,随着冻土层厚度的增加,场地卓越频率呈增大趋势,但变化不大,场地地震反应呈减小趋势。

By using the theories of random vibration and the finite element method of dynamical analysis, the stochastic earthquake responses of the permafrost ground of Qinghai-Tibet Railway were analyzed, the stochastic earthquake characteristics of the ground were calculated, and the effects of the thickness of frozen soil on the stochastic characteristics of the earthquake motion were studied. As a result of an example, the natural frequencies and the maximum earthquake responses of this ground for various conditions were obtained. The results showed that the natural frequencies of ground would increase but its earthquake responses would decrease with the increase of the thickness of frozen soil.