Analysis Of Moisture And Heat Response Characteristics And Stability Of Dump Under Rainfall And Evaporation

Landslide is a common natural disaster,which is closely related to the change of water content in the slope.Rainfall and evaporation are the triggering conditions for the change of water content in the slope.At present,the research on the slope stability under the condition of rainfall has been more in-depth,but few literatures consider the influence of evaporation on the slope stability.In order to study the response law and stability change of slope under rainfall and evaporation conditions,this paper takes a waste dump slope as the research object,and sets up a variety of climatic conditions that comprehensively consider the temperature,humidity,wind speed,rainfall and other factors,as well as the rainfall single factor conditions corresponding to the climatic conditions.With the help of the VADOSE/W module of GeoStudio,the wet conditions of slope under different climatic conditions are analyzed.The SEEP/W module is used to analyze the seepage characteristics under the condition of rainfall single factor.The difference of seepage field and safety factor between climate and rainfall is analyzed.The stability of slope is evaluated by reliability method.Slope / W module is used to simulate the reinforcement of waste dump slope and optimize the reinforcement scheme.The main conclusions are as follows:(1)Under various climatic conditions,the change of slope water content shows that the shallow surface response is strong and timely,the deep response is unclear and lag,the soil water content increases with rainfall,decreases with evaporation and drought,and the change rate depends on rainfall and temperature.The change of soil temperature is related to its depth,outside air temperature and soil moisture content,among which the outside air temperature is dominant.Evaporation is related to humidity and air temperature.The lower the humidity is,the greater the evaporation is.The higher the temperature is,the greater the evaporation is.The evaporation is also related to the soil moisture content.(2)Comparing the seepage field of slope under the condition of climate and rainfall single factor,we can see that the change of soil moisture is related to the depth and rainfall.The larger the rainfall,the larger the range of water content.The deeper the slope is,the smaller the variation range of soil moisture is,and the more obvious the lag effect is.The reason is related to the seepage path.Under the condition of heavy rainfall,the water content of slope under the climatic condition is higher than that under the rainfall condition,which may be caused by evaporation to increase the pore gas pressure,which has a blocking effect on the infiltration of rainwater.Under the condition of overcast and rainy,The water content of slope under rainfall condition is higher than that under climate condition.which may be caused by the unknown blocking effect and evaporation.(3)In case of heavy rainfall,The safety factor of slope under climate condition is smaller than that under rainfall condition,and the reason is related to retardation effect;in case of overcast rain,the safety factor of slope is climate condition > rainfall single factor condition The safety factor of the slope is that the climate condition is greater than the rainfall single factor condition,and the reason is related to the decrease of rainfall infiltration caused by evaporation.After rain,the soil moisture dissipation is accelerated by dry evaporation,and the increase of slope safety factor is larger than that of rainfall single factor.The safety factor can not reflect the actual safety level of the slope,so it is necessary to use the reliability analysis method to further discuss the stability of the slope.(4)The safety factor of slope can be effectively improved by using anchor and anti slide pile.According to the optimization of the reinforcement schemes of the waste dump slope in this paper,the optimal anchor angle is 15 °,the optimal anchor spacing is vertical distance of 3M,horizontal distance of 1.5m,and the anchor should be arranged close to the shear position of the potential sliding surface in the middle and lower part of the slope.When the location parameter of anti slide pile is 0.3,the stabilization effect is the best and the cost is the least.