Numerical Study on Bottom Boundary Effect in Quasi-Static Intrusion into Granular Media
Based on the spherical discrete element method,this paper studies the bottom boundary effect of granular media,simulates the quasi-static intrusion of rigid body cylinders into particle media with limited thickness to the bottom boundary,and explores the relationship between the resistance of intrud-er and the depth of intrusion.The results show that the resistance-depth curve of the cylindrical quasi-static intrusion particle layer to the bottom of the pool has a linear hydrostatic pressure in the front sec-tion and an exponential growth form in the back section near the bottom boundary.However,there are fluctuations in resistance within a few particle sizes from the bottom,and the wavelength is approxi-mately the same length as the particle diameter.Furthermore,the particles in the inverted conical curing zone connected to the cylindrical bottom have dynamic renewal.The curing zone collapses when the in-trusion is close to the bottom boundary,where the local particle blocking determines the resistance growth trend.Additionally,the particle force chain below the bottom of the cylinder is transformed into a"bottom-bottom"force chain between the bottom of the cylinder and the bottom of the particle pool when it approaches the bottom boundary.The decrease in the average number of particles after the force chain is squeezed explains the volatility of the resistance oscillation.
granular mediaquasi-static intrusionbottom boundary effectmesoscopic force chaindiscrete element simulation
万方数据
维普
