降雨-库水联合作用下的丹江口库区金岗滑坡机理研究OA

Rainfall and reservoir water level changes are important factors inducing the landslides of accumulation layers in reservoir areas.Since different types of landslides in reservoir areas have different response processes to hydrodynamic factors,the instability mechanisms of reservoir bank landslides are complex,resulting in different disaster-causing modes.Taking Jingang landslide in Danjiangkou Reservoir area as an example,based on the study of the landslide characteristics and its deformation patterns,the basic geological model of this landslide was established.Accordingly,the finite element Geo-Studio software was used to analyze the stability status of the landslide under the influence of rainfall and reservoir water level changes.Combining with monitoring results,the deformation mechanism of such accumulation layer landslides in Danjiangkou Reservoir area was revealed.The results are as follows:①The influence of reservoir water on landslides is mainly concentrated at the front,primarily induced by seepage.Rainfall mainly affects the middle and rear parts of the landslide,primarily by softening the soil.Under the combined action of rainfall and reservoir water,the landslide may undergo progressive sliding and failure characterized by traction at the front and pushing at the rear.②When the reservoir water level rises or falls rapidly,hydrodynamic pressures directed toward the interior and exterior of the slope are formed within the slope body,significantly affecting the stability of the landslide.However,such effects can be mitigated through artificial regulation of the reservoir water level.③The deformation mechanism of the landslide can be generalized as a combination of reservoir water softening and hydrodynamic pressure.When exposed to water,expansive clay gradually softens,leading to cracking and subsidence on the surface of the landslide due to expansion and contraction.Heavy rainfall and sudden drops in reservoir water level directly induce landslide failure by affecting the internal seepage field and stress field.This study provides important insights into the formation mechanism of accumulation layer landslides in reservoir areas,which has significant theoretical and practical implications.