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An Improved Two-Load Method for Whole-Field Complete Photoelastic Fringe Analysis

Published online by Cambridge University Press:  05 May 2011

T. Y. Chen*
Affiliation:
Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan 701, R.O.C.
H. L. Lee*
Affiliation:
Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan 701, R.O.C.
Y. C. Chou*
Affiliation:
Department of Mechanical Engineering, National Cheng Kung University, Tainan, Taiwan 701, R.O.C.
*
* Professor
** Graduate student
** Graduate student
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Abstract

An improved two-load method for whole-field complete determination of photoelastic parameters is presented. The dark-field isoclinic images are used to determine the isoclinic angles. Using two isoclinic maps obtained from two different loads effectively compensates the indeterminable points. The use of dark-field and light-field photoelastic images for normalization extends the two-load method to analyze dark-field photoelastic fringe patterns and avoids model movement. Larger errors on the determined fringe orders are further reduced by a least-squares quadric fitting. The results are compared well to the theoretical ones. Further comparison of the improved two-load method and the two-wavelength method are given.

Type
Technical Note
Copyright
Copyright © The Society of Theoretical and Applied Mechanics, R.O.C. 2005

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References

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