Anisotropic damage in quasi-brittle solids: Modelling computational issues and applications
The authors develop a unified continuum damage model for progressive anisotropic degradation taking into account the frictional sliding over internal crack surfaces. In order to ensure the practical applicability of the model, a small number of constants are included. The modelling of multiple mesocrack growth leads to volumetric dilatancy and non-symmetrical strength effects, which allows to describe the crack closure under predominantly compressive loads. The authors consider rotating loading and damage axes with highly complex loading paths. The integration of the corresponding constitutive equations is performed by using a stable algorithm with incremental steps of initial elastic nature and plastic corrections. The material parameters are identified using a triaxial compression test with a loading path. The authors introduce a second-order tensor of orientation and decohesion surfaces which, for general anisotropy, becomes a fourth-order tensor which is able to describe the damage force as derivative of energy in the space of damage tensor components, the damage criterion, and the rate damage evolution law. The formulations are further extended to include plasticity induced by frictional blocking of crack lips. Additional potentiality arises for quasi-brittle materials. Finally, the authors give an application which concerns rock-like solids with torsion-compression.
scientific article; zbMATH DE number 1487185
scientific article