Analysis of the Influence of Intermittent Rainfall on Red Bed Landslide in Yuanma Basin
The red bed slope of Yuanma Basin has the characteristics of small rock dip angle and small side slope angle,and it is in a relatively stable state in natural state.Water has a great influence on the mechanical properties of red sandstone.Rainfall infiltration will cause the saturation of soil layer inside the slope to increase,the matrix suction to decrease,and the water head generated in the crack will have a flat thrust on the slope.In order to study the temporal and spatial effects of rainfall on slope stability,the whole process of Dahuaping landslide was reconstructed through field investigation of existing landslides in Yuanma Basin and quantitative and qualitative analysis was carried out by means of numerical simulation,and the effects of early and late rainfall on slope under different intensification were compared and analyzed.The results show that the influence of rainfall in the early stage is reflected in the reduction of matrix suction caused by infiltration,the continuous rise of water pressure in cracks,and the continuous decline of safety factor but failing to reach the critical value of landslide.The recovery of safety factor of slope after rain stop has a lag,and the lag is more obvious with the smaller the rainfall in the early stage.The influence of late rainfall is reflected in that the higher the rainfall,the more easily the surface seepage is formed,and the sliding force is increased.If there is water in the original fissure,then the safety factor of slope during the rain stop stage changes slowly.
red bed soft rock landsliderainfall patternGeostudio numerical analysis
万方数据
维普
