3D mode discrete element method with the elastoplastic model

Abstract

The three-dimensional mode-deformable discrete element method (3MDEM) is an extended distinct element approach under the assumptions of small strain, finite displacement, and finite rotation of blocks. The deformation of blocks is expressed by the combination of the deformation modes in 3MDEM. In this paper, the elastoplastic constitutive relationship of blocks is implemented on the 3MDEM platform to simulate the integrated process from elasticity to plasticity and finally to fracture. To overcome the shortcomings of the conventional criterion for contact fracturing, a new criterion based on plastic strain is introduced. This approach is verified by two numerical examples. Finally, a cantilever beam is simulated as a comprehensive case study, which went through elastic, elastoplastic, and discontinuous fracture stages.

Keywords

mode discrete element method, elastoplastic, numerical method, discontinuum, contact

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Acknowledgment

The authors gratefully acknowledge the financial support provided by the National Natural Science Foundation of China (Nos. 50539020, 90715041 and 40974063).

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg