Discrete Element Method Based Numerical Simulation Of Semi-Rigid Base Erosion Damage

The material of semi-rigid base is lack of anti-erosion ability which cause insufficient of carrying capacity of semi-rigid base. Currently, the study on erosion damage mechanism of semi-rigid is mainly focused on macro-theoretical description of the process of erosion damage in China and other counties. The research methods also are laboratory tests, The numerical simulation study of the erosion damage mechanism of semi-rigid base is inadequate. This article establish a semi-rigid material unconfined compression test model based on Discrete Element Method(DEM), and through the discrete element method and computational fluid dynamics coupling method(DEM-CFD) establish DEM-CFD erosion model.Based on Discrete Element Method(DEM), this article uses the PFC2 D software to reco nstruct three structures(skeleton dense,skeleton pores, dense suspension) of cement stabilize d semi-rigid material, and establish it’s visual discrete element model and writing the FISH la nguage programs to tracking the loading process of stress and strain, thus simulating semi-rigi d base of unconfined compressive strength test. By adjust the microscopic parameter of mode l, so that the simulation results are consistent with laboratory test results, and we can get thre e different microscopic parameters of three structures, through analyzing the loading internal f orce of three structures, and the internal pressure of suspended dense structure is more unifor m than others. Contact force loading process chain of three skeletal structure were analyzed, t he results showed that the skeletal structure’s chain force is bigger than others, the mos t obvious effect of the skeleton. Use the model of FIXED COARSE-GRID FLUID SCHEM E of Optional Features in PFC2 d to set different scour area for semi-rigid discrete element mo del, The DEM-CFD erosion model of skeleton dense structure and suspended dense structur e use compressive strength loss rate to evaluate the anti-erosion performance of semi-rigid b ase material. Study on erosion properties of pavement structure in primary antibody. The artic le was introduced into the fluid domain and used PFC2 d software incorporation of fluid coupl ing in PFC2 d module to simulate the anti-erosion performance of semi-rigid base. Setting th e measurement circle below the plate gap to measure the coordination number of particle and porosity in the measurement circle during the process, we can evaluate the anti-erosion abil ities of the three structures through the changes of coordination number of particle and poro sity. The simulation results show that the anti-erosion performance of skeleton pores is bette r than others. The anti-erosion performance of dense suspension is worst.This article established a semi-rigid base micromechanics erosion model, which use the numerical simulation to simulate erosion evolution of semi-rigid base and explore the mechanical response and damage mechanisms from micromechanics perspective. Research results provide a theoretical basis for improving the durability of the base, and improving the structure of the road pavement design methods.