Particle Flow Code Simulation Of The Relationship Between The Thickness And The Inclination Angle On Rough Inclined Plane

The occurrence of disasters such as avalanches,landslides,and debris flows in nature generally shows the motion properties of general continuous fluids.In fact,the material in the sliding body is discrete and discontinuous,which is essentially different from the continuous fluid.All these disasters occur on the inclined plane and to be a dense particle fluid.A single particle shows its solid property and obeys Newton's law of motion.The damage of particle accumulation body and its motion show the property of fluid.There are collision and friction between particles on flow and accompanied by energy conversion and dissipation.So far,there is no simple and universal theory to summarize the collapse mechanism of granular media,and many problems remain to be solved.In this paper,the model of flow on the rough inclined plane is simulated by Particle Flow Code(PFC^2D),to demonstrate the relationship between the thickness and the inclination angle on the rough inclined plane,and study the collapse behaviour of particle on the inclined plane.The contact model between ball-ball,and ball-wall adopts the Linear Contact Model and Rolling Resistance Linear Contact Model.Firstly,the model of repose angle is established,to calculate the internal friction angle characterizing the macro material,and determine the micro parameters of the contact model between ball-ball.Considering the effect of the size effect on the model construction,the particle flow model of the slope was established.The micro parameters of the angle of repose was used to establish the contact model between ball-ball and ball-wall.The results of model are compared with those of previous laboratory studies to verify the rationality of the model.Finally,the static particle layer of the inclined plane was disturbed to study the collapse behaviour of the particles after being disturbed.Through the simulation of the numerical model,it is obtained:?1?Through the model simulation and calculation of the repose angle,two contact models respectively obtain the repose angle of the two materials:The Rolling Resistance Linear Contact Model has an repose angle of 23.5°;the Linear Contact Model has an repose angle of 18.1°.?2?The thickness decreases with the increase of the inclination angle,which shows an exponential decay relationship.?3?By tilting the inclined plane to the point where the particle layer begins to collapse,we can determine the threshold value of the particle collapse of the plane,and divide the relationship between the thickness and the inclination angle into three phase areas:no flow,stable flow and unstable flow.?4?When the inclined plane is tilting to a certain inclination angle,we disturb the static particle layer.The particles are found to expand upward at the location of the disturbance.After the particle layer was disturbed,the particles at the rear of the disturbed position lost their support,began to collapse,and tumble down along the plane.The simulation results of this numerical model is similar to the previous laboratory.By comparing and analysing the results of the discrete element simulation of the micro structure of the particles with the experimental results of the physical experiment,it is possible to establish the relationship between the physical and mechanical properties of the macro material and the micro parameters of the material.It can promote the study of particulate matter,reveal the debris flow,landslide,avalanches and other natural disasters and contribute to the study of the movement mechanism.