A 2D discrete particle model for rock fracture: formulation and calibration
DOI:
https://doi.org/10.14195/2184-8394_129_4Keywords:
Particle model, Rock fracture, Parametric studiesAbstract
Detailed rigid particle models have been proposed for modelling fracture in quasi-brittle materials. In the present study, a 2D rigid particle model that has been developed to study fracture phenomena in rock is adopted. The particle assemblies are created using a particle generation algorithm that generates polygonal shaped particles based on the Laguerre Voronois of the circular particle gravity centres of an initial circular particle assembly. The particles are considered to interact through a multiple contact point model where the contact width and the contact location are defined given the Voronoi tessellation. The particle model is validated against known triaxial and Brazilian test results of a granite rock. Several parametric studies are presented showing the influence of the elastic and strength micromechanical parameters on both the macroscopic elastic and strength properties. Finally, a reference is made to the relevance of adopting a bilinear tensile/shear softening contact model in order to obtain coherent ultimate tensile values in direct tensile tests and in Brazilian tests.
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