Run-out Simulation Of Soil Landslide Using Material Point Method

As one of the most common geological hazards in nature,landslides often cause severe loss of life and property to human society.However,it is difficult to analyze and study the soil landslides accurately and effectively by experimental means owing to their high burst and long distance movement.At present,numerical calculation is mainly performed to study the soil landslides.Material Point Method(MPM)is one of the meshless numerical analysis method,which can effectively simulate the material behavior and the run-out characteristics of landslides.From the point of view of numerical method and numerical model optimization,the material point model was established for the simulation of the whole process of soil landslide based on the MPM.In comparison with the oedometer test and the benchmark experiment results,the proposed MPM model was verified.Based on the established numerical models,the whole process of two types of soil landslides induced by collapsing and heap loading were simulated and refined.The main contents of the article include:(1)Based on the MPM,a single-layer and single-phase which is suitable for simulating large-scale deformation of soil under dry conditions and a single-layer and two-phase soil-slide model for saturated conditions were established(2)Through the application of Mohr-Coulomb constitutive model,the inversion of the whole movement of the Huaxian landslide and catastrophic landslide at the Shenzhen Landfill was achieved.The results show that the whole run-out process of collapsing soil landslide can be divided into four stages,namely start-up stage,acceleration stage,deceleration stage and accumulation stage.Moreover,soil strength parameters,pore water pressure and initial accumulation form have significant influence on the failure and movement process of loose accumulation body.(3)A simplified model for surcharge-induced landslides was established to reveal the deformation and failure mechanisms and the movement characteristics when soil slopes are under surcharge.The results show that the soil strength parameters and the load level have significant influence on the movement process,and they have a strong linear correlation with the characteristic parameters of the landslide movement,in which the internal friction angle has a greater influence than the cohesion.Also,the result can be applied to predict the degree of disaster caused by the landslide.