Effect of pore shape on uniaxial compressive behaviour of porous rock-like materials: DEM simulation

Abstract

The pore shapes of porous rock-like materials are not circular but complex and diverse，constituting a critical factor influencing their mechanical properties and failure characteristics. In this study, the effects of pore angularity and aspect ratio on the mechanical behaviour of porous rock-like materials under uniaxial compression were quantitatively analyzed using the Discrete Element Method (DEM). Numerical models containing pores of various shapes were constructed as Voronoi polygon aggregates to more realistically simulate material fracture. The results show that with increasing angularity or aspect ratio, both the uniaxial compressive strength and elastic modulus decrease in distinct patterns, while Poisson's ratio remains unchanged. Moreover, higher angularity or aspect ratio not only leads to cracks initiation at sharp corners and causes the crack paths to deviate from the axial loading direction, but also results in an increase in both the total crack length and the number of fragments. Finally, the evolution of the microstructure, including contact forces and the spatial distribution of stress, was analyzed to assess the influence of pore shape on microscopic characteristics.