If you are interested in obtaining a free copy of the ABAQUS UMAT source code in FORTRAN for the Complete Gurson Model, please contact Prof. Zhiliang Zhang.

Here you can also download a pdf copy of Prof. Zhiliang Zhang's PhD thesis which contains the detailed formulations of the algorithms he developed to implement the complete Gurson model in ABAQUS and the the theory back the complete the complete Gurson model: A Practical Micro-Mechanical Model-Based Local Approach Methodology for the Analysis of Ductile Fracture of Welded T-Joints.

Here you can download a manual prepared for guiding the compuatational exercises in the NTNU course - TMM4160 Fracture Mechanics. This manual covers the minimum you need to use ABAQUS to calculate the fracture mechanics parameters (K, J. CTOD).

Manual for ABAQUS Based Computational Fracture Mechanics Exercises