The relationship between Ct and contour integrals under small-scale transient creep

Abstract In this paper, the relationship between the C t and contour integrals for small-scale transient creep conditions is established, via elastic-creep finite element analysis. It is found that the C t integral is similar to the contour integral value evaluated roughly at the creep zone size defined as the boundaries where time-dependent effective creep strains equal the instantaneous effective elastic strains and measured normal to the crack plane at the crack tip.