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Experimental Mechanics

, Volume 2, Issue 12, pp 359–365 | Cite as

Stress distribution about a slowly growing crack determined by photoelastic-coating method

Test procedure is verified by determining that insufficient shear transfer through the plastic thickness resulted in errors less than 10 percent
  • William Gerberich
Article

Abstract

An experimental stress-analysis technique using a birefringent coating is reported for determining the stress distribution about a slowly growing crack. The maximum error of the test method for a large strain gradient is found to be less than 10 percent. For a plate with an internal crack, the experimentally determined stress distribution compares favorably with two numerical solutions. Comparison of stresses about an internal or double-edge crack to those about a single-edge crack indicates that the isochromatics bend over to about 45 deg with the plane of the crack in the former and are inclined at about 60 deg in the latter. Also, the stresses for a single-crack tip vary as the inverse square root of the radius, while the stresses for a double-crack tip follow anr−1/4 law more closely.

Keywords

Mechanical Engineer Fluid Dynamics Stress Distribution Maximum Error Large Strain 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Society for Experimental Mechanics, Inc. 1962

Authors and Affiliations

  • William Gerberich
    • 1
  1. 1.Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadena

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