Abstract A micro-crack elastoplastic damage model under compressive loading is presented in this work. Interactions among the cracks are modeled by self-consistent approach in which each crack experiences a stress field different from that acting on isolated cracks. The propagation of wing crack in the micro-crack tip is characterized for rock damage, and the wing crack length is obtained using Newton iteration based on the strain energy density for mixed-mode fracture. The distribution of micro-cracks is presented by the absolute volume strain with the two-parameter Weibull statistical model. The damage evolution variable of rock is employed by the distribution of micro-cracks and stress release volume described by length of wing-crack. Voyiadjis’s strain hardening function is employed as the plastic yield function and plastic potential function. The elastoplastic damage model with its numerical algorithm is proposed and the code of elastoplastic damage model is implemented by using return mapping implicit integration algorithm. The influence of rock confining pressures on the damage response in the elastoplastic damage model is analyzed. The results show that the proposed elastoplastic damage model agrees well with the experimental results for one rock test under uniaxial compression.
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Received: 29 August 2011
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