Logarithmic singularity at crack tips in piezoelectric media

The Lekniskii-and Stroh-formalism are often used to study the crack-tip sigularity ofa two-dimensional anisotropic material, such as purely elastic material and piezoelectricmedia. The present work investigates the logarithmic singularity at crack tips inpiezoelectricity. For a semi-infinite crack in an anisotropic piezoelectric media, it is shownthat both stresses and electric displacements at crack tips may be in the order of r-1/2, orr1/2lnr, r1/2ln2r, r-1/2ln3r, as r→0, where r is the distance from crack tip to field point, de-pending on which conditions are satisfied.