EFFECTS OF PROCESS ZONES ON CRACK INTERACTIONS

The problem of interaction among cracks, including the effects of proc ess zones, is studied. The Dugdale-type cohesive-zone model is extende d to mixed-modes of loading and is then used to evaluate the size of p rocess zones. The interaction is considered by applying uniform normal and shear tractions on each crack surface caused by the remaining cra cks. The magnitude of these interaction tractions relative to far-fiel d stresses reflects the intensity of the interaction. The effect of pr ocess zones on the magnitude of interaction tractions is studied by co mparing them with the corresponding elastic values. It is shown that p rocess zones generally enhance the interaction, but effective properti es are not altered significantly.