Numerical Simulation Study On The Catastrophic Law Of Loess Slopes Under Rainfall Infiltration Based On The Secondary Development Of FLAC3D

Due to its own structural characteristics such as porosity,low density,and water sensitivity,loess disasters occur continuously,and rainfall is the main factor affecting the destruction of loess slopes.Loess is a typical unsaturated soil,and its unsaturated soil properties have a great influence on slope stability.With the progress of rainfall,the infiltration of rainwater caused the water content of the loess slope and the suction of the matrix to change constantly,which caused the deformation of the loess to be deformed or even unstable.The K3+0-400 m section of Shuohuang Railway is located in Shenchi County,Xinzhou City,Shanxi Province.It is a prone area for loess landslide geological disasters.This Paper takes this as a research background.The secondary development of FLAC3 D by the understanding of unsaturated soil,Make it conform to the theory of unsaturated soil seepage and the stability calculation of unsaturated soil.The numerical simulation of loess slope is carried out to simulate the slope failure process under different rainfall conditions,and the slope failure process caused by rainfall under different angles and heights is simulated.Finally,the rainfall experiment of loess slope is carried out,which is the stability of loess slope under rainfall conditions.for reference.Taking the law of damage under different rainfall conditions as the research purpose,the following conclusions are drawn:(1)Rainwater infiltration capacity weakens gradually with increasing depth and rainfall time(2)With the increase of rainfall intensity,the infiltration depth of rainwater is larger,but the increase is small,and the rainfall intrusion depth decreases with the increase of rainfall duration.(3)The greater the rainfall intensity,the greater the saturation from the surface of the slope to the wet front,the low rainfall intensity,the saturation zone on the surface of the slope,and the saturation zone when the rainfall intensity is greater than the saturated infiltration velocity.(4)The horizontal stress of the slope foot is the maximum position of the entire slope,and it is also the maximum position of the horizontal displacement.The position of the vertical maximum displacement position is at the top of the slope,and the position of the slope foot is the most dangerous position.Within a certain range,with the greater the rainfall intensity,The greater the increase in stress.(5)The greater the rainfall intensity,the earlier the landslide occurs and the smaller the landslide formed.(6)The slope angle and height increase,the earlier the slope is landslide,the larger the landslide body,and the more easily the displacement is abrupt.