ASYMMETRIC STEADY-STATE SOLUTIONS FOR A CRACK IN A VISCOELASTIC FIELD OF PURE BENDING

The problem of a crack in a viscoelastic material subjected to an alternatively positive and negative asymmetric bending moment is considered. The asymmetry refers to the fact that the bending moment spends more time and has a greater maximum in one direction, say positive, than in the other. Steady-state solutions which close at only one end of the crack are studied. This is a specifically viscoelastic effect, which would not occur in the elastic limit. It would seem to suggest that biased crack propagation patterns are more likely in a viscoelastic material than in an elastic material subject to the same asymmetric fluctuating bending moment. Numerical results are presented for a standard linear model.