Simulation of ductile crack growth test of pipe

Abstract

In this study, the ductile fracture behavior was analytically reproduced for circumferentially through-wall cracked pipes. The purpose is to evaluate the reliability of structural equipment from simulation analysis using the finite element method. As a method, simulation analysis was performed by six different approaches, including nucleation, growth, and coalescence of voids simulated by Gurson model and GTN model, Simple model which is a simple model used in general FEM analysis, ductile crack propagation using VCCT model, ductile crack propagation using stress modified fracture strain (SMFS) model, ductile crack propagation using Truss model to simulate pseudo crack propagation behavior. And, the simulation analysis results were compared with previously performed ductile crack propagation test. Among them, VCCT model and Truss model also calculated the amount of crack propagation. Discrepancies between the experimental maximum loads and calculated maximum loads were about 5% in the minimum case. In the analysis using the Truss model, although the load in the load-Load Point Displacement curve was smaller than the load measured in the test, an approximate curve of the test could be reproduced. Also, the VCCT model was able to match the crack propagation start point in the experiment with the calculated crack propagation start point.