Simulation Implementation on the Direction Prediction of Crack Propagation Based on the First Principal Stress

The study attempts to present a new finite element method to implement the direction prediction of crack extension for 2D and 3D cracks based on the maximum tensile stress (MTS) criterion by identifying the first principal stress direction. Especially in the 3D crack propagation, this paper gave a detailed and innovative research method to overcome the challenge of direction prediction on crack extension. The maximum principal stress of the node of crack tip and its neighboring nodes were calculated to determine the increment and the direction of crack tip respectively. Some examples of complex crack propagation were performed under a variety of mixed fracture modes based on linear elastic analysis by ANSYS software. A reasonable evaluation was executed and the advantages of this method were analyzed in detail.

Strain Injection Techniques for Modeling 3D Crack Propagation

This work presents some novel results obtained by using the strain injection techniques for modeling crack propagation in challenging 3D benchmark tests. The techniques were already tested and validated by static and dynamic simulations in 2D ADDIN EN.CITE ADDIN EN.CITE.DATA [ HYPERLINK \l "_ENREF_1" \o "Dias, 2012 #1526" 1-4], so the main goal of this paper is to verify if the most important advantages of the method, low computational cost and independence of the results on the finite element mesh, are kept in 3D. The methodology, implemented in the finite element framework, consists essentially in injecting those elements that are going to capture the cracks with some enhanced strain modes for improving the performance of the elements for modeling propagating material failure.