ASTM D7078 / D7078M – 12 : Standard Test Method for Shear Properties of Composite Materials by V-Notched Rail Shear Method
This shear test is designed to produce shear property data for material specifications, research and development, quality assurance, and structural design and analysis. Either in-plane or interlaminar shear properties may be evaluated, depending upon the orientation of the material coordinate system relative to the loading axis. Factors that influence the shear response and should therefore be reported include: material, methods of material preparation and lay-up, specimen stacking sequence, specimen preparation, specimen conditioning, environment of testing, specimen alignment and gripping, speed of testing, time at temperature, void content, and volume percent reinforcement.
In anisotropic materials, properties may be obtained in any of the six possible shear planes by orienting the testing plane of the specimen with the desired material plane (1-2 or 2-1, 1-3 or 3-1, 2-3 or 3-2). Only a single shear plane may be evaluated for any given specimen. Properties, in the test direction, which may be obtained from this test method, include the following:
Shear stress versus engineering shear strain response,
Ultimate shear strength,
Ultimate engineering shear strain,
Shear chord modulus of elasticity,