Evaluation of Failure Criteria Based on Stress Intensity Factors and Stress Components to Predict Crack Propagation Trajectory in Rock Mediums

Document Type : research - paper

Authors

Shahrood University of Technology

Abstract

   The commonly used failure criterion based on stress intensity factors is compared with new developed stress based failure criterion to predict crack growth trajectory and the advantages and disadvantages of both criteria are discussed using some examples. To obtain displacement vector and strain and stress tensors, the element free Galerkin method (EFGM) is used. The visibility criterion is applied to model cracks and the M-integral method is employed to calculate the stress intensity factors. Two examples are considered to evaluate the mentioned failure criteria. The stress intensity factors obtained from EFGM show good agreement with the results of finite element and analytical solutions. The failure criterion based on stress intensity factors only can predict the initial crack trajectory however the stress based failure criterion can predict the complete crack growth path and its predictions coincide very well with numerical and experimental results.      

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