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库岸深层老滑坡在季节性降雨和周期性库水位变动联合作用下往往表现出间歇性复活特征。在这一复活过程中,滑动期与间歇期交替出现,滑带土经历不同速率的剪切和不同时长的固结。从滑动期内残余强度的剪切速率效应、间歇期内峰值抗剪强度的恢复特征以及间歇期过渡到滑动期的孔隙水压力触发过程3个方面着手,建立了描述库岸深层老滑坡间歇性复活的动力学方程。塘角村1号滑坡滑带土试样的环剪试验结果显示:残余强度在较小速率范围内表现出负速率效应,而当剪切速率达到一定值后残余强度不再减小,且有微弱增长趋势;峰值强度在短时间内有较明显的恢复,但在较小位移后衰减至残余强度;孔隙水压力触发剪切破坏的发生滞后于所施加的水压力,这一滞后过程为孔隙水压力的扩散过程。基于试验成果,根据所建立的动力学方程,对库岸深层老滑坡间歇性复活的动力学机制进行了讨论,从而为此类滑坡的预测和防灾减灾提供有价值的参考。
The deep old landslide on the bank coast often shows intermittent resurrection characteristics under the joint action of seasonal rainfall and periodic changes of reservoir water level. In this resurrection process, the sliding period alternates with the intermittent period, and the sliding zone soil undergoes shear at different rates and consolidation at different time scales. From three aspects of the shear rate effect of residual strength during sliding period, the recovery characteristics of peak shear strength during intermittent period, and the pore-water pressure triggering process during the transitional period to the sliding period, an inter- Resurrection kinetic equation. The results of ring-shear tests on the soil samples of the landslide in the Tangjiao 1 landslide show that the residual strength shows a negative rate effect at a relatively small rate and the residual strength no longer decreases when the shear rate reaches a certain value The trend of peak shear strength is obvious in a short period of time, but decay to residual strength after a small displacement. The occurrence of pore water pressure triggered shear failure lags behind the applied water pressure, Water pressure diffusion process. Based on the experimental results, the dynamic mechanism of the intermittent resurrection of the old deep landslide in the reservoir bank is discussed based on the established dynamic equations, which will provide valuable reference for the prediction and disaster prevention and reduction of such landslides.