Quasi-static crack extension in fiber-reinforced composites subjected to thermal shock is analyzed using the boundary integral equation method, in combination with sensitivity analysis techniques. Buekner's formulation is employed to evaluate the stress intensity factor in a cracked body. This method eliminates the need for special element types to model the crack tip, as well as the use of a large number of elements near the cracked zone of interest. A numerical procedure involving sensitivity analysis techniques based on the adjoint structure approach has been developed to evaluate the energy integrals in the cracked body. Gradients of the functionals of response quantities with respect to variables such as the crack length, necessary for the evaluation of fracture parameters, are determined directly by this method. The numerical differentiation used in other numerical methods, such as the finite element method, which requires the repeated solution of the equations for different crack sizes is avoided. Results for stress intensity factors as a function of crack length are presented for various composite systems. These results are in good agreement with analytical results and results from the finite element method. The present approach results in significantly improved computational efficiency.
All Science Journal Classification (ASJC) codes
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering