Mode I crack initiation in orthotropic viscoelastic plate under biaxial loading

Анотація

The subcritical propagation of a crack in orthotropic viscoelastic plate under time-constant biaxial external loading is investigated on the basis of generalization of Leonov – Panasyuk – Dugdale crack model for the case of orthotropic materials, which satisfy a strength condition of arbitrary form. The crack is directed along one of the anisotropy axes with external loads being applied parallel and perpendicularly to it. For finding the rheological characteristics of composite material the method of operator continued fractions is applied. The relationships for determining duration of incubational and transitional periods of crack propagation are determined on the basis of the Volterra principle and solution of the corresponding elastic problem. The influence of the biaxiality of external loading on the safe loading and the subcritical crack growth is analyzed within the framework of the critical crack opening displacement criterion.