An extended FE strategy for transition from continuum damage to mode I cohesive crack propagation

摘要

An integrated strategy is proposed for the simulation of damage development and crack propagation in concrete structures. In the initial stage of damage growth, concrete is considered to be macroscopically integer and is modeled by a non-symmetric isotropic non-local damage model. The transition to the discrete cohesive crack model depends on the local mesh size and is driven by an analytical estimate of the current bandwidth. When a crack is introduced in the model an extended finite element approach is used to follow the propagation path, independent of the background mesh. The proposed methodology is tested on a notched tension specimen and then applied to the analysis of a wedge splitting test.