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Separation of Photoelastic Principal Stresses by Analytical Evaluation and Digital Image Processing

Published online by Cambridge University Press:  05 May 2011

C.W. Chang*
Affiliation:
Department of Civil Engineering, Chung Hua University, HsinChu, Taiwan 30012, R.O.C
P.H. Chen*
Affiliation:
Commissioner of Public Works Department, HsinChu City Government, Taiwan
H.S. Lien*
Affiliation:
Department of Civil Engineering, Chung Hua University, HsinChu,, Taiwan 30012, R.O.C.
*
* Associate Professor
**Ph.D. student
**Ph.D. student
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Abstract

A new method for separation of isochromatic stresses is presented. This method is derived from the series solution of self-equilibrium polynomial stress equations and compatibility equations. The equations are quantified in terms of a stress function as the photoelastic stresses. Those equations are combined with the digital image processing technique and the linear regression curve fitting method to determine the contour equations of isochromictics and isoclinics fields. The solution of those equations provides a relationship between the normal stresses/shear stress and the photoelastic stress (maximum shearing stress). The results are consistent with the results obtained by the finite element method.

Type
Articles
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2009

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