中文摘要：

以某水电站为工程背景，建立该水电站地下厂房大型岩体洞室群有限元-无限元耦合动力计算模型。在洞室群开挖稳定后所形成的二次应力场和地震动荷载联合作用下，进行不同地震动输入方向下的大型岩体洞室群地震反应研究。研究结果表明，地震动斜入射对地下岩体洞室群的动力反应和稳定性有不利的影响，在进行类似的大型地下岩体洞室群地震动安全评价时应考虑地震动输入方向的影响。

英文摘要：

The finite-infinite element coupling model of a large underground rock cavern groups is set up which is located in the western of China. Firstly, in order to obtain the reasonable secondary geostress field, the rock cavern is excavated under the loading of gravity. Then its seismic response is studied under the combined loadings of the secondary geostress formed after excavation and the seismic motion considering different incident angles. Simulated results indicate that the obliquely incident earthquake waves dramatically influence the seismic response of underground rock cavern groups, for example, the distribution of stress and the plastic zone of the cavern groups The incident angle of seismic wave should be taken into account in the seismic safety assessment of the similar underground rock cavern groups.