AN INTERMEDIATE ASYMPTOTIC SOLUTION OF THE COUPLED CREEP-DAMAGE CRACK PROBLEM IN SIMILARITY VARIABLES

Abstract

The class of self-similar solutions to coupled (creep-damage) crack problems is considered. The constitutive model is based on continuum damage mechanics. The conventional Kachanov-Rabotnov creep-damage theory is utilized to study the asymptotic behavior of damage in the region very near the crack tip. The totally damaged zone where the damage (integrity) parameter reaches its critical value is assumed to exist in the vicinity of the crack tip. Using the similarity variable the asymptotic solutions to mode I and mode III crack problems are obtained. The asymptotic stress, creep strain rate and damage fields near the crack tip are analyzed by solving nonlinear eigenvalue problems resulting in a new far stress distribution. The configurations of the totally damaged zone governed by the new far stress field are found and analyzed.