TY - JOUR

T1 - On the computation of mixed-mode K-factors for a dynamically propagating crack, using path-independent integrals J'k

AU - Nishioka, T.

AU - Atluri, S. N.

N1 - Copyright:
Copyright 2014 Elsevier B.V., All rights reserved.

PY - 1984

Y1 - 1984

N2 - The path-independent integral J'k, which has the meaning of energy release rate in elastodynamic crack-propagation, is used to numerically obtain the mixed-mode dynamic stressintensity factors for a crack propagating in a prescribed direction with a prescribed velocity. Moving isoparametric (non-singular) elements are used to model crack propagation. Even though J' is a vector integral and hence is coordinate invariant, the desirability of using specific coordinate systems to improve the accuracies of the numerical solutions for K-factors is pointed out. Two procedures for extracting the mixed-mode K-factors from the J' integral for a propagating crack are given. It is found that the component of J' along the crack-axis, i.e. J'10, is always equal to or greater than the product of a crack-velocity-function and the component normal to the crack-axis, J'20. Several examples of a slanted crack are presented to demonstrate the practical utility of the J' integral. A discussion is also presented concerning the velocity factors for dynamic K-factors, and energy release rate, in a finite body.

AB - The path-independent integral J'k, which has the meaning of energy release rate in elastodynamic crack-propagation, is used to numerically obtain the mixed-mode dynamic stressintensity factors for a crack propagating in a prescribed direction with a prescribed velocity. Moving isoparametric (non-singular) elements are used to model crack propagation. Even though J' is a vector integral and hence is coordinate invariant, the desirability of using specific coordinate systems to improve the accuracies of the numerical solutions for K-factors is pointed out. Two procedures for extracting the mixed-mode K-factors from the J' integral for a propagating crack are given. It is found that the component of J' along the crack-axis, i.e. J'10, is always equal to or greater than the product of a crack-velocity-function and the component normal to the crack-axis, J'20. Several examples of a slanted crack are presented to demonstrate the practical utility of the J' integral. A discussion is also presented concerning the velocity factors for dynamic K-factors, and energy release rate, in a finite body.

UR - http://www.scopus.com/inward/record.url?scp=0021619701&partnerID=8YFLogxK

U2 - 10.1016/0013-7944(84)90128-0

DO - 10.1016/0013-7944(84)90128-0

M3 - Article

AN - SCOPUS:0021619701

VL - 20

SP - 193

EP - 208

JO - Engineering Fracture Mechanics

JF - Engineering Fracture Mechanics

SN - 0013-7944

IS - 2

ER -