Iosipescu Shear Test Apparatus Applied to Wood Composites


  • John J. Janowiak
  • Roy F. Pellerin


Iosipescu, in-plane, transverse, shear strength, wood composites


In-plane and transverse (through-the-thickness) shear strength properties were evaluated for three wood composite materials. A modified Iosipescu test apparatus was used to determine shear strength relative to the six possible material orientations. In-plane shear was also characterized using ASTM D1037-87 test standards. The Iosipescu shear test method was developed originally for metals testing. However, different forms of the test device have evolved for purposes of shear evaluation with numerous nonisotropic materials being evaluated. Previous research for various materials has shown satisfactory results with repeatability and apparent shear failure. The current research specifically utilized the University of Wyoming version of the original shear test device. Iosipescu test results for in-plane shear strength were comparable to values derived from the ASTM test method. Transverse shear strength values were found to exceed the magnitude of previously published ASTM test results. Greater directional or material orientation differences were observed for transverse shear properties.


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