Multiple parallel cracks interaction problem inpiezoelectric ceramics

This paper has two goals[ First\ we propose the {pseudo!traction electric displacement| method for solving the interaction problem of multiple parallel cracks in transversely isotropic piezoelectric ceramics[ Secondwe present a fundamental understanding for the role that the electric displacement loading plays in the interaction problem[ Detailed comparisons between the results under the compound mechanical electric loading conditions and those derived under purely mechanical loading conditions are performed[ It is shown that the mechanical fracture parameters such as the stress intensity factors are no longer independent of the electric loading as they would be in single crack problems[ Quite contrary\ the electric displacement loading has a signi_cant in~uence on the stress intensity factors\ the total potential energy release rate and the mechanical strain energy release rate[ This important conclusion is mainly due to the interaction e}ect\ i[e[one of the multiple cracks releases the stresses and disturbs the electric _elds near the other crack[ It is also found that there are some special relative locations for the multiple parallel cracks at which the electric displacement loading has no e}ect on the Mode I stress intensity factor[ However\ the mechanical strain energy release rate has no such a property