Numerical Study of Material Damage Asymptotics near the Crack Front under Creep
L.V. Stepanova, O.N. Belova, D.V. Chapliy, Yu.S. Bykova
Samara National Research University named after S.P. Korolev, Samara, Russia
Keywords: damage, stress field asymptotics, crack, creep, power law of damage accumulation
Abstract
Results of computations of continuity and stress fields (in the Lagrangian formulation) near the crack front under creep conditions are presented and discussed. Calculations were performed using the finite element method to determine asymptotic distributions of stresses and continuity (damage) near the edge of the cut. For various material constant values, the shape of the damaged material zone under creep developing ahead of the crack tip was determined. Analysis of radial stress distributions obtained from finite element computations shows that the damage accumulation process alters the asymptotic behavior of stresses near the crack tip in a material described by a power-type governing equation. It was shown that, in the absence of damage accumulation, the numerical solution approaches the Hutchinson-Rice-Rosengren asymptotics, whereas accounting for the damage accumulation process affects the stress field near the cut or crack. Using finite-element radial stress and continuity distributions, characteristic sizes of zones dominated by different asymptotics near the crack tip can be determined.
|
