Mixed mode crack growth in elasto-plastic-creeping solids using XFEM

Abstract In this work, an extended finite element based fully implicit algorithm is proposed to predict the creep deformation and creep crack growth in elasto-plastic-creeping solids. The effect of stress relaxation and redistribution due to creep strain is captured through elasto-plastic-creep analysis. In creep crack growth analysis, mostly C ∗ is used to compute the creep crack growth which includes only extensive creep whereas C ( t ) -integral includes small-scale creep, transition creep and extensive creep. Thus, in the present study, creep crack characterization parameter C ( t ) -integral is evaluated using XFEM to compute creep crack growth rate. The mixed mode stress intensity factors are evaluated using domain based interaction integral approach to estimate the crack growth direction. Various numerical issues related to history dependency of plasticity and creep are properly addressed. To validate the present approach, various numerical problems are solved and the predicted creep deformation and creep crack growth results are compared with the experimental observations.