A generic computational model for three-dimensional fracture and fragmentation problems of quasi-brittle materials. (English) Zbl 1477.74107
Summary: Fracture and fragmentation in three dimensions are of great importance to understand the mechanical behaviour of quasi-brittle materials in failure stress states. In this paper, a generic computational model has been developed in an in-house C/C++ code using the combined finite-discrete element method, which is capable of modelling the entire three-dimensional fracturing process, including pre-peak hardening deformation, post-peak strain softening, transition from continuum to discontinuum, and explicit interaction between discrete fragments. The computational model is validated by Brazilian tests and polyaxial compression tests, and a realistic multi-layer rock model in an in situ stress condition is presented as an application example. The results show that the computational model can capture both continuum and discontinuum behaviour and therefore it provides an ideal numerical tool for fracture and fragmentation problems.
Keywords:
finite-discrete element method; fracture; fragmentation; Mohr-Coulomb criterion; pre-peak hardening; post-peak strain softeningReferences:
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