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地裂缝是黄土地区的一种典型地质灾害,地震波在地裂缝场地中的传播规律是工程界比较关心的一类问题。为了研究地震波在地裂缝处的传播规律,引用西安地区地裂缝界面的等效刚度系数和裂缝面的接触面连续条件,基于运动方程的基本解答,在考虑转换波产生的前提下得出了求解西安地裂缝处地震波透反射系数的频域方程组。对入射角、入射波频率和地裂缝介质等效力学参数的变化对地震波传播规律的影响进行了分析。结果表明,地裂缝对地震波的传播起到了一定的高频滤波作用,当入射波频率较低时波动的传播主要以透射波为主;等效法向刚度只影响P波的传播,等效切向刚度对P波和SV波都有影响;相对于法向刚度,切向刚度的变化对的透反射系数的影响更为明显。
Ground fissures are a kind of typical geological disasters in the loess area. The propagation of seismic waves in the ground fissure sites is a kind of problem that the engineering community is more concerned about. In order to study the propagation law of seismic waves in ground fissures, the equivalent stiffness coefficient of ground fissure interface in Xi’an area and the continuous contact surface condition of fissures are referenced. Based on the basic solutions of motion equations, Frequency - domain equations of seismic reflection coefficient of ground fissures in Xi’an. The influence of the change of incident angle, incident wave frequency and the equivalent mechanical parameters of ground fissures on the propagation of seismic waves is analyzed. The results show that the ground fissures play a certain role in the high frequency filtering of the seismic wave propagation. When the incident wave frequency is low, the wave propagation is dominated by the transmitted wave. The equivalent normal stiffness affects only the P wave propagation. The equivalent tangential The stiffness affects both the P wave and the SV wave. The influence of the variation of the tangential stiffness on the transreflection coefficient is more pronounced than the normal stiffness.