Abstract
The interaction between the isopescu shear-test specimen and the modified Wyoming shear-test fixture was investigated. This involved three areas of study. First, strip strain gages were applied to the specimen contact surfaces to measure strains induced by the fixture. While it has generally been assumed that the fixture induces an asymmetric load into the specimen, the measured strains indicated a nonasymmetric loading. Second, the effect of an out-of-plane moment, externally applied to the fixture, on gage section shear strains was observed. The shear strains observed were small leading to the conclusion that the fixture is very resistant to out-of-plane moments. Finally, the effect of fixture misalignment on the observed shear modulus was determined. The results indicate that the observed shear modulus increased significantly for slight amounts of misalignment. Therefore, experimental techniques should be modified to include a check for misalignment. Beyond this, it is suggested that the fixture design be modified to prevent misalignment and to achieve an asymmetric loading of the specimen.
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References
Iosipescu, N., “New Accurate Procedure for Single Shear Testing of Metals,”J. Mat.,2 (3),537–566 (1967).
Walrath, D.E. andAdams, D.F., “The Iosipescu Shear Test as Applied to Composite Materials,”Experimental Mechanics,23 (1),105–110 (1983).
Walrath, D.E. and Adams, D.F., “Analysis of the Stress State in an Iosipescu Shear Test Specimen,” Report UWME-DR-301-102-1, Dept. of Mechanical Engineering, Univ. of Wyoming (June 1983).
Abdallah, M.G. andGascoigne, H.E., “The Influence of Test Fixture Design on the Iosipescu Shear Test for Fiber Composite Materials,”Test Methods for Design Allowable for Fibrous Composites: 2nd Volume, ASTM STP 1003, ed. C.C. Chamis, ASTM, Philadelphia, 231–260 (1989).
Lee, S. andMunro, M., “Evaluation of Testing Techniques for the Iosipescu Shear Test for Advanced Composite Materials,”J. Comp. Mat.,24,419–440 (1990).
Ho, H., Tsi, M.Y., Morton, J. andFarley, G.L., “An Experimental Investigation of Iosipescu Specimen for Composite Materials,” EXPERIMENTAL MECHANICS,31,328–336 (1991).
Morton, J., Ho, H., Tsi, M.Y. andFarley, G.L., “An Evaluation of the Iosipescu Specimen for Composite Materials Shear Property Measurement,”J. Comp. Mat.,26 (5),708–750 (1992).
Micro-Measurement, “Catalog 500: Strain Gage Technical Data,” Micro-Measurement Group, Inc.
Grimes, G.C. and Adams, D.F., “Investigation of Compression Fatigue Properties of Advanced Composites,” Northop Tech. Rep. No. NOR 79-17 (Oct. 1979).
Wilson, D.W., “Evaluation of the V-notched Beam Shear Test Through an Inter-Laboratory Study,”J. Comp. Tech. & Res.,12 (3),131–138 (1990).
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Odom, E.M., Blackketter, D.M. & Suratno, B.R. Experimental and analytical investigation of the modified wyoming shear-test fixture. Experimental Mechanics 34, 10–15 (1994). https://doi.org/10.1007/BF02328436
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DOI: https://doi.org/10.1007/BF02328436