In the field of computational modeling of material failure mechanisms, a classical brittle damage model commonly leads to an ill-posed system of equations in numerical realizations, and further yields a divergent numerical solution. An established gradient enhanced approach has been demonstrated to be a powerful and efficient tool to address the issue of localized singularities. The work at hand formulates a brittle damage model based on a gradient micromorphic regularization approach, which, in particular, incorporates a novel Representative Crack Element (RCE) framework to address physically reasonable crack kinematics in the damaged zone. The deformations in the micro cracks within the macro damage zone, which include crack opening, closing (stiff contact), shearing as well as mixed aforementioned deformations, can be comprehensively captured. Thus, the work at hand attempts to resolve the strong-discontinuity problem (within cracks) based on a regularized damage model in a numerically robust manner. The present constitutive model of the gradient damage coupled problem is derived based on a thermodynamic consistent algorithm. In the meantime, a minimization algorithm of the RCE virtual power is employed for the solution of the unknown crack deformations. The formulation is implemented into the context of the conventional Finite Element Method framework. Several representative and meaningful numerical examples are studied to demonstrate the capability of the present model.
|Journal||Computer methods in applied mechanics and engineering|
|Publication status||Published - 1 Sept 2022|