Experimental Mechanics

, Volume 4, Issue 6, pp 153–159 | Cite as

Isopachic patterns by the moiré method

Highly satisfactory correlation is found between results obtained with proposed method and those obtained by other experimental methods
  • Pericles S. Theocaris


Interference between a grating, with line rulings of a density of 500 lines/in., and its shadow is used for the determination of isopachics in plane-stress problems.

The procedure consists in using a white collimated light beam obliquely incident to the model. A reference master grating is attached to the surface of the model and the interference pattern of this grating and its shadow, produced by the oblique light beam, is photographed in a position normal to the model. Interference patterns before and after loading of the specimen allow the determination of isopachics.


Mechanical Engineer Fluid Dynamics Light Beam Interference Pattern Line Ruling 


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Copyright information

© Society for Experimental Mechanics, Inc. 1964

Authors and Affiliations

  • Pericles S. Theocaris
    • 1
  1. 1.Laboratory for Testing MaterialsAthens National Technical UniversityAthensGreece

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