ABAQUS subroutines for the simulation of fatigue crack propagation in quasi-brittle materials using phase field cohesive zone approach

This document presents ABAQUS subroutines and instructions for utilizing the phase field cohesive zone framework in simulating fatigue crack propagation in quasi-brittle materials within the ABAQUS software. The implementation involves the use of the user material subroutine (UMAT) and the heat flow subroutine (HETVAL) at the integration point level. The approach leverages the correspondence between the heat transfer law and the phase field balance equation. An illustrative example of fatigue simulation, demonstrating mixed-mode crack propagation in concrete, is also included.