Studying the Effect of Rock Shape on Brittle Fracture Pattern Using a Mesh-free Method SPH

摘要

Numerical modelling can assist in understanding and predicting complex fracture processes. Smoothed Particle Hydrodynamics (SPH) is a particle based Lagrangian method which is particularly suited to the analysis of fracture due to its capacity to model large deformation and to track free surfaces generated. A damage model is used to predict the fracture of elastic solids. The damage parameter represents the volume averaged micro-fracture of the volume of material represented by an SPH particle. Evolution of damage is predicted using the strain history of each particle. Damage inhibits the transmission of tensile stress between particles, and once it reaches unity, it is unable to transmit tensile stress, resulting in a macro-crack. Connected macro-cracks lead to complete fragmentation. In this paper we explore the ability of an SPH based damage model to predict brittle fracture of rocks during impact. Rock shape is found to have considerable influence on the fracture process, the fragment sizes, the energy dissipation during impact, and the post-fracture motion of the fragments.