On Phase-Field Modeling of Fracture in a Computational Framework

Phase-field models are widely regarded as one of the most versatile methods to numerically solve a variety of physical phenomena related to Continuum Mechanics. In this dissertation they are applied to some notable brittle fracture mechanics case studies, in order to validate their robustness and reliability by comparing produced numerical outcomes with experimental results. Firstly a 1D benchmark is defined, giving particular attention to modeling definitions (e.g. how degradation functions depends on damage rise and growth) and stability concepts, investigating under which conditions damage localizes. For this one-dimensional case an original MATLAB code was implemented, whose logic and structure are broadly deepen. Numerical results are then produced for 2D case studies, involving circular holes and re-entrant corners influence on structural resistance: computationally we have leveraged Abaqus/FORTRAN coupling potentialities through UEL subroutines implementation. From a comparison with experimental datasets, our outcomes show a credible qualitative predictions of failure stresses for the considered geometries. This work opens up to extend simulation results on damage trajectories predictions, in order to furnish to the analyzed structures also a morphological fracture characterization.