Accession Number : ADA260927


Title :   Continuum and Micromechanics Treatment of Constraint in Fracture


Descriptive Note : Final rept.,


Corporate Author : ILLINOIS UNIV AT URBANA DEPT OF COMPUTER SCIENCE


Personal Author(s) : Dodds, R H , Jr ; Shih, C F ; Anderson, Ted L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a260927.pdf


Report Date : Jan 1993


Pagination or Media Count : 47


Abstract : This report explores the fundamental concepts of the J-Q description of crack-tip fields, the fracture toughness locus and micromechanics approaches to predict the variability of macroscopic fracture toughness with constraint under elastic-plastic conditions. While these concepts derived from plane-strain considerations, initial applications in fully 3D geometries are very promising. Computational results are presented for a surface cracked plate containing a 6:1 semi-elliptical, a=tl4 flaw subjected to remote uniaxial and biaxial tension. Crack-tip stress fields consistent with the J-Q theory are demonstrated to exit at each location along the crack front. The micromechanics model employs the J-Q description of crack-front stress to interpret fracture toughness values measured on laboratory specimens for fracture assessment of the surface cracked plate. The computational results suggest only a minor effect of the biaxial loading on the crack tip stress fields and, consequently, on the propensity for fracture relative to the uniaxial loading.... J-integral, Q-stress, Fracture toughness, Surface flaw biaxial loading, Finite element analysis.


Descriptors :   *MICROMECHANICS , MODELS , FINITE ELEMENT ANALYSIS , CRACKING(FRACTURING) , CRACKS , INTEGRALS , THEORY , PLASTICS , LOCUS , J INTEGRALS , APPROACH , EXITS , TOUGHNESS , SURFACES , PLATES , TENSION , LABORATORIES , VALUE


Subject Categories : Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE