Thermoelectromechanical Response of a Piezoelectric Strip with Two Parallel Cracks of Different Lengths

The thermoelectromechanical fracture of a piezoelectric material strip with two parallel cracks of different lengths under electric and thermal loadings is considered. The crack faces are supposed to be insulated thermally and electrically. Fourier transform techniques are used to reduce the mixed boundary value problems to two systems of singular integral equations. The singular integral equations are solved by using the Gauss-Jacobi integration formula. Numerical calculations are carried out, and detailed results are presented to illustrate the influence of the parameters of indicating the crack lengths, the crack location and the crack spacing on the stress and electric displacement intensity factors. The results for the temperature and thermal stress distributions are also included. From the numerical results, we can find that the normalized intensity factors are under the great influence of the geometric parameters. Especially, the interaction between two different length cracks is complicated.