Stress intensity factor for an elliptic inclusion in orthotropic laminates subjected to freeze-thaw: Model verification

Verifications and applications of an analytical model developed previously for the calculation of mode-I stress intensity factor of a pre-existing crack in an orthotropic composite structure due to the phase transition of trapped moisture are presented in this paper. The verifications are based on comparisons of the stresses in an elliptic elastic inclusion and the stress intensity factor with a special case of isotropy (for which there exists an analytical solution) and with finite element analysis for the case of orthotropy. The results indicate that the stress state in a slender elliptic elastic inclusion can be used to approximate the stress field at the crack face, which could subsequently be adopted to determine the stress intensity factor. Analyses of the delamination and fatigue life prediction for freeze-thaw cycling are provided as specific applications of the model.