Investigations of the cemented sand behavior using the DEM simulations

In this paper, the numerical simulation by the discrete element method (DEM), is used to investigate the underlying mechanisms that govern the cemented sand behavior, such as the enhanced strength and volumetric dilation due to cementation and strain localization. The simulation results suggest that all of the particles in the bonding network jointly share the load and many micro force-chains associated with cementation are generated. A more stable and stronger force-chain network subjected to smaller force/stress concentrations is therefore formed, which ultimately minimizes the risk of force-chain buckling and leads to higher strength. At large strains, the bonded cluster can help stabilize the particle arch and maintain large voids for the volumetric dilation. Different local responses in cemented sand gradually become distinct after the peak strength. Strain softening and volumetric dilation are observed inside the shear band; however, the region outside the shear band undergoes elastic unloading. Such a completely different local strain response ultimately produces a clear and persistent shear band, i.e., strain localization.