中文摘要：

选取三峡水库区地震频发的兴山县一典型厚层堆积型滑坡为研究对象,以实测库水位波动与地震发生时间点关系为基础,并参照V度地震烈度,采用静力-渗流-动力多场耦合3D数值模拟方法,对滑坡变形机理进行研究。结果表明：（1）地震作用与库水位波动密切相关,不利的渗流条件和地震动荷载作用相互叠加,渗流场-动力场耦合作用共同导致滑坡体发生变形;（2）堆积层滑坡体结构相对均质,无显著不良地质单元,除堆积体临空面附近外,其对地震波几乎无放大效应;（3）V度地震烈度条件下,连续地震对堆积层滑坡变形量的影响有限且收敛,但仍有必要对滑坡体变形进行长期监测。

英文摘要：

Seismic actions in the head region of the Three Gorges Reservoir（TGR）have increased significantly since the beginning of dam impoundment.Coupled with cyclical water level fluctuation,the deformation mechanism of landslides beside TGR are worthy of research.A typical accumulative landslide located in Xingshan County was selected as a case study in this paper.Three typical adverse conditions were determined by monitoring relationship between the water level fluctuation and time of seismic occurrence.Then,using a seismic intensity of V degree,a multifield coupling numerical simulation was conducted to determine the deformation mechanism of the landslide.The results of the simulation afford the following conclusions：（1）Seismic action is closely related to water fluctuation,while superposition of adverse flow conditions and seismic load,the coupling effect of the seepage field and dynamic field causes a landslide deformation.（2）The structure of the debris landslide is relatively homogeneous,except for the region close to the free face of body of debris.There are no significant undesirable geologic elements and seismic amplification is not reflected in the debris.Furthermore,the mechanical parameters of debris and bedrock are quite different,thus the boundary of debris and bedrock is also a deformation border.（3）When the seismic intensity attains the V degree,a deformation landslide caused by continual earthquakes is limited and convergent,but long-term deformation monitoring for landslides is necessary.