Interface crack between two different viscoelastic media

The plane (including antiplane) problem of an interfacial crack between dif ferent viscoelastic (including viscoelastic and elastic) media is considere d. By using the Laplace transform method, the viscoelastic problem is reduc ed to an associated elastic one. The corresponding elastic analysis results in the viscoelastic solutions in the transformed field. The crack tip fiel ds and fracture parameters of the viscoelastic interface crack are derived through an approximate Laplace inverse transform method. As an example, num erical calculations for an interfacial crack between viscoelastic and elast ic materials are carried out. It is shown that the simple formulae of the c rack line (and tip) fields and fracture parameter (energy release rate) of the viscoelastic interface crack, derived by the approximate method, are qu ite accurate. When the bimaterial is subject to a remote uniform and consta nt tensile loading, the normal stress along the crack line (including tip) is almost time independent. In contrast, the relative crack surface displac ements and crack energy release rate do change with time, and are very much dependent on the creep compliance of the viscoelastic material. The tenden cies of the crack advancing along the interface, and kinking out of the int erface, are estimated and discussed. (C) 2001 Elsevier Science Ltd. All rig hts reserved.