KSME Journal

, Volume 5, Issue 1, pp 22–27 | Cite as

Accuracy improvement technique for measuring stress intensity factors in photoelastic experiment

  • Tae-Hyun Baek
  • Christian P. Burger


Fracture coefficients, together with the exact origin of the crack, were extracted from data sets produced an overdeterministic system solved by an iterative least squares method. Power series type williams equations were used in the analyses. The accuracy evaluation indicated that the first four terms of williams equations are sufficient to describe the stress field in the vicinity of the crack tip for both mode I and mixed mode cases. Experimental study showed that the first two terms of williams equations, which are the same as the modified westergaard equations, cannot be used to extract mixed mode fracture parameters accurately within the data collection region of 0.07 <r/a <0.30, where r and a are radial coordinate and crack length for an edge crack, respectively.

Key Words

Stress Intensity Factor (SIF) Crack Tip Analysis Photoelastic Experiment Williams Equations Mixed Mode Fracture Parameter Fracture Mechanics 


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Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1991

Authors and Affiliations

  • Tae-Hyun Baek
    • 1
  • Christian P. Burger
    • 2
  1. 1.Department of Mechanical DesignKunsan National UniversityChonbukKorea
  2. 2.Department of Mechanical EngineeringTexas A & M UniversityCollege StationUSA

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