Experimental Mechanics

, Volume 39, Issue 3, pp 236–241 | Cite as

Sensitivity of the shear gage to normal strains

  • X. Niu
  • P. Ifju
  • A. Abdel-Hadi


This paper documents an experimental study that was conducted to demonstrate the sensitivity of the shear gage to the presence of normal strains. The shear gage is a specially designed strain gage rosette that measures the average shear strain in the test section of notched specimens such as the losipescu, Arcan and compact shear specimens. These specimens can have complicated stress states with high shear and normal strain gradients. To evaluate the sensitivity of the shear gage to normal strains, shear gages were tested on an Arcan specimen. The Arcan specimen is a notched specimen that can be loaded in pure shear (90 deg), pure tension (0 deg) and at intermediate 15- deg increments. The shear modulus for an aluminum specimen was determined at each of these loading angles. It was found that the gages display nearly zero sensitivity to normal strains (ɛx,ɛy). Moiré interferometry was used to document the shear and normal strain distributions in the test section and to provide an independent method for determining the average shear strain. These results reinforce the robust nature of testing with the shear gage.

Key Words

Shear gage moiré interferometry Arcan shear specimen losipescu shear specimen Mohr's circle 


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Copyright information

© Society for Experimental Mechanics, Inc. 1999

Authors and Affiliations

  • X. Niu
    • 1
  • P. Ifju
    • 1
  • A. Abdel-Hadi
    • 1
  1. 1.Department of Aerospace Engineering, Mechanics and Engineering ScienceUniversity of FloridaGainesville

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