New Numerical and Experimental Approach for Mixed Mode Crack Growth in Wood by Mθv Integral

摘要

This paper deals with a numerical design of a new timber specimen called Mixed Mode Crack Growth (2MCG), assuring mixed modes fractures during crack growth process. The 2MCG specimen is obtained by a combination of stable Double Cantilever Beam (DCB) specimen and Constant Tension Shear (CTS) specimen. The analytical formulation, given by a generalization of the M-integral parameter called MO , and resolved by finite element software Castem, is presented. The developed integral, based on conservation laws, path independent integral and bilinear form of displacement fields, is explained. As numerical results, a final form of the new specimen is shown. Also, the stability range is proved by the decrease of elastic energy release rate versus crack length in opening mode, shear mode and mixed mode solicitations.