For example, we should be able to identify our major concerns in a problem.
So, my point view is that, at current stage, we still rely on our knowledge and experience to solve such problems. Although, someone (or some FEA packages) have claimed their approaches are blah blah., however, when you really touch it, you will know it is not as you expected. To my understanding, simulation of the arbitrary crack propagation is still remained unsolved as one of the most challenging topics in solid mechanics. SB, Progressive crack growth analysis using interface element based on the virtual crack closure technique, Finite Elements in Analysis and Design, 42(2006): 977-984.ģ. Farahmand B, Saff C, Xie De, and Abdi F, Estimation of fatigue and fracture allowables for metallic materials under cyclic loading, 48h AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics & Materials Conference, AIAA-2007-2381. If you are interested, you may read my papers for details.ġ. Xie D and Waas AM, Discrete cohesive zone model for mixed-mode fracture using finite element analysis, Engineering Fracture Mechanics, 73(2006): 1783-1796.Ģ. Xie D and Biggers, Jr. Therefore, I developed ABAQUS UEL based on VCCT (DCZM) to study the crack propagation since they are mesh independent for crack problems. You will never get converged results using stress criteria.įor this reason, we should avoid using stress/strain criteria, though ABAQUS has this option. The finer the mesh, the higher the stress. As a result, the stress value will depend on FEA mesh size. As we all know that at the crack tip, the stress is singular.