T-stresses in bimaterial isotropic strips subjected to generalized end loadings

The non-singular T-stress terms at the tip of a semi-infinite interfacial crack in an isotropic bimaterial strip subjected to generalized end loadings are derived by referring to six elementary loading modes and using two techniques. For equal thickness layers with the second interfacial Dundurs’ parameter equal to zero, the two-dimensional elasticity problem is reduced to a scalar Riemman problem and solved using the Wiener-Hopf method. The conservation property of the mutual integral and far- and local-field approximations of the displacements along the boundaries of the strip are applied to derive expressions for the T-stresses applicable also to strips with unequal thickness layers; the method can be generalized to multilayered systems and arbitrary material combinations. Coupled with existing solutions for stress intensity factors and root compliances, knowledge of the T-stress terms allows a complete description of the behavior of bimaterial layers with interfacial cracks. This has relevant applications which include, for instance, the sizing of specimens to characterize the interfacial fracture properties.