Unsaturated Seepage Characteristics and Stability Analysis of Tail-Water Slope under Heavy Rainfall
In order to explore the stability of the tailwater slope of pumped storage power station under the action of heavy rainfall,the distribu-tion and change of the seepage field of the slope under the condition of heavy rainfall are simulated based on the saturation-unsaturated seepage theory,and combined with the seepage calculation results,the strength reduction method is used to analyze the stability of the slope under the condition of rainfall.The results show that when the rainfall intensity exceeds the saturated permeability coefficient of soil,the transient saturation zone appears first at the foot of slope and the lower part of the slope surface.With the increase of rainfall duration,the wetting front moves inward to the slope.During long-term rainfall,the variation of slope stability coefficient is mainly determined by two factors:one is the decrease of effec-tive stress caused by the increase of pore water pressure and the other is the increase of sliding force caused by the increase of saturated bulk den-sity of surface soil.The stability coefficient of slope decreases continuously during the rainfall process,and suddenly changes after 3d rainfall.In the early stage of rainfall,the slope potential slip surface is arc-shaped,and the sliding surface depth becomes shallow with the increase of rain-fall duration.In the late stage of rainfall,the potential slip surface of the slope appears to be distributed along the wetting peak A linear slip sur-face,and as rainfall continues to act,the slip surface moves toward the interior of the slope along with the wetting front.
万方数据
维普
