中文摘要：

以三峡库区某复活型深层老滑坡为例,着重分析前缘监测点累积位移与库水位变动及降雨量的相关性,发现该复活型深层老滑坡前缘的变形与库水位下降具有明显的对应关系,并存在一定时间的滞后。根据太沙基有效应力原理与Mohr-Coulomb强度准则,揭示了诱发因素影响下的孔隙水压力扩散是这一滞后响应的关键机制。对于极限平衡状态下的库岸深层老滑坡,由降雨及库水位变动产生的孔隙水压力增量需经一定时间段后才能传递到滑动面处,并影响滑动面处的孔隙水压力进而产生滑动速度,且这一滞后时间与滑坡体的水力扩散系数及滑坡体厚度密切相关。基于理论分析,对取自于该滑坡前缘的滑带土进行了孔隙水压力扩散的模拟试验,证实了该机制过程的合理性。同时,该机制的揭示对解决当前滑坡位移预测模型尚不能考虑滞后效应这一问题具有参考价值。

英文摘要：

A typical reactivated ancient landslide in the Three Gorges Reservoir was taken as a case study and the relations among the displacement increment, rainfall and reservoir water level fluctuation were an- alysed. It was found that there is an obvious correspondence between the deformation in frontal part of the landslide and the drawdown of reservoir water level. A certain time of delayed response was also found. According to Terzaghi effective stress principle and Mohr-Coulomb strength criterion, the diffusion of pore water pressure which is caused by the inducing factors is the key mechanism of the delayed response in this paper. For the deep-seated ancient reservoir landslide in the limit equilibrium state, the increment of pore water pressure caused by rainfall and reservoir water level fluctuation needs a certain time to transmit to the sliding surface, and then affects the pore water pressure which causes a sliding velocity. In addition, the delayed time is closely related to the hydraulic diffusivity and thickness of the sliding mass. Based on the theoretical analysis, the test of pore water pressure diffusion on the soil sample which collected from the frontal part of the landslide was performed to prove the reasonable of the mechanism revealed above. What＇s more, the mechanism can provide the help to solve the problem which does not consider the delayed response in the present displacement prediction model.