A micromechanics-based variational phase-field model for fracture in geomaterials with brittle-tensile and compressive-ductile behavior
نویسندگان
چکیده
This paper presents a framework for modeling failure in quasi-brittle geomaterials under different loading conditions. A micromechanics-based model is proposed which the field variables are linked to physical mechanisms at microcrack level: damage related growth of microcracks, while plasticity frictional sliding closed microcracks. Consequently, hardening/softening functions and parameters entering free energy follow from definition single degradation function elastic material properties. The evolution opening microcracks tension leads brittle behavior mode I fracture, compression/shear ductile II fracture. Frictional endowed with non-associative law, crucial aspect that considers effect dilation allows realistic responses non-vanishing dissipation. Despite variationally consistent formulation presented using notions balance stability, following energetic rate-independent systems. response first described, followed by numerical implementation procedure several benchmark finite element simulations. results highlight ability describe tensile, shear, mixed-mode as well brittle-to-ductile transition. key result that, virtue micromechanical arguments, modes can be captured, without resorting usual heuristic modifications considered phase-field literature. thoroughly discussed reference previous studies, experimental evidence, analytical fracture criteria.
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ژورنال
عنوان ژورنال: Journal of The Mechanics and Physics of Solids
سال: 2022
ISSN: ['0022-5096', '1873-4782']
DOI: https://doi.org/10.1016/j.jmps.2021.104684