A theory of crack initiation and growth in viscoelastic media II. Approximate methods of analysis

摘要: Starting with equations developed in Part I for the opening mode of displacement, simple, approximate relations are derived predicting time fracture initiation and crack tip velocity linearly viscoelastic media. First we use assumption that second derivative logarithm creep compliance respect to is small (which normally valid materials); next derive a relation between instantaneous values stress intensity factor. This result then used examine some characteristics growth behavior. Finally, results obtained separate problem at which propagation initiates.