Study of the influence of adaptive refinement strategy parameters to phase-field modeling of fracture

Resumo

The phase-field model has consolidated itself as a promising tool to handle complex cracks. In this model, the crack is represented in a diffuse form where the phase-field variable indicates the degradation of the material. To better approximate this variable, extremely refined meshes are required, which demands expensive computational efforts. In this work, an adaptive refinement strategy is adopted to phase-field modeling of fracture. In this strategy, the domain is initially discretized with a coarse finite elements mesh and during the analysis the crack regions are automatically replaced by a Smoothed Point Interpolation Methods (SPIMs) and refined. The SPIM is a meshfree method that possess the kronecker delta property. This property facilitates the application of boundary conditions and guarantees direct coupling with finite elements. Different criteria can be used to identify the crack regions. Furthermore, parameters such as refinement level and size of the substitution region are adopted in the strategy. For the SPIM, different smoothing domains and support nodes selection are applied. The aim of this work is to evaluate the influence of these adaptive strategy parameters on the crack propagation. Numerical simulations are performed and the results are compared with the previously refined FEM and with results available in the literature.