DEM for investigating the mechanical properties of porous rock-like materials under uniaxial compression

Porous rock-like materials are widely used in civil engineering. The pore is an important factor affecting the mechanical properties of a material. In this paper, the effects of the number of pores, Np, and pore size, Rs, on the mechanical properties of porous rock-like materials under uniaxial compression were studied quantitatively via the DEM. Numerical models containing different numbers and sizes of pores were divided into Voronoi polygons to construct samples. The macroscopic characteristics showed that with increasing Np and Rs, the uniaxial compressive strength and elastic modulus significantly decreased, while Poisson's ratio dramatically increased. Furthermore, as Np and Rs increased, the microcracks concentrated into macroscopic cracks, and the number of fragments decreased. Moreover, the anisotropy of the crack orientation was weakened. Finally, the evolution of the microstructure anisotropy, including the contact, contact force magnitude, and normal and tangential contact forces, was evaluated to probe the effect of the pores on the microscopic characteristics.