Experimental Mechanics

, Volume 21, Issue 1, pp 41–48 | Cite as

Dynamic stress-intensity factors for unsymmetric dynamic isochromatics

The mixed-mode, near-field state of stress surrounding a constant-velocity crack is used in an overdeterministic, least-square procedure to determineKI,KII and σox from dynamic photoelastic patterns surrounding the running crack. The procedure is used to determine the mixed-mode stress-intensity factors associated with crack branching and crack curvingfrom dynamic photoelastic patterns surrounding the running crack. The procedure is used to determine the mixed-mode stress-intensity factors associated with crack branching and crack curving
  • A. S. Kobayashi
  • M. Ramulu


The mixed mode, near-field state of stresses sourrounding a crack propagating at constant velocity is used to derive a relation between the dynamic stress-intensity factorsKI,KII, the remote stress component σ ox and the dynamic isochromatics. This relation, together with an over-deterministic least-square method, form the basis of a datareduction procedure for extracting dynamic,KI,KII and σ ox from the recorded dynamic photoelastic pattern surrounding a running crack. The overdeterministic least-square method is also used to fit static isochromatics to the numerically generated dynamic isochromatics. The resultant staticKI,KII and σ ox are compared with the corresponding dynamic values and estimats of errors involved in using static analysis to process dynamic isochromatic data are obtained. The data-reduction procedure is then used to evaluate the branching stress-intensity factor associated with crack branching and the mixed-mode stress-intensity factors associated with crack curving.


Mechanical Engineer Fluid Dynamics Constant Velocity Stress Component Mixed Mode 
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Copyright information

© Society for Experimental Mechanics, Inc. 1981

Authors and Affiliations

  • A. S. Kobayashi
    • 1
  • M. Ramulu
    • 1
  1. 1.Department of Mechanical Engineering, College of EngineeringUniversity of WashingtonSeattle

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