Measurement of Principal Stress Direction by Photoelastic Phase Shifting Method

광탄성 위상이동법을 이용한 주응력 방향 측정법

  • 김명수 ;
  • 김환 ;
  • 백태현
  • Published : 2004.12.01


In photoelasticity, the directions of principal stresses are given by isoclinic fringe patterns. In this study, photoelastic theory is represented by Jones calculus and the photoelastic 8-step phase shifting method is described. A feasibility study using computer simulation is done to get isoclinics from photoelastic fringes of a circular disk under diametral compression. Fringe patterns of the disk are generated from the stress-optic law. The magnitudes of isoclinics obtained from the fringe patterns of computer simulation and experiment are compared with those of theory. The results are close between them. Then, the 8-step phase shifting method is applied to get distributions of isoclinics along the specified lines of a cuved beam plate under tensile load. Experimental results obtained from the phase shifting method were compared with those of finite element analysis (ANSYS). It is confirmed that measurement of isoclinic distributions is possible by use of photoelasitc phase shifting method.


Photoelasticity;Phase Shifting Method;Isoclinics Fringe;Principal Stress Direction


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