In this test arrangement, which is described in ASTM D 5379, a specimen notched on both sides is clamped in a special device which is held longitudinally.
When compressed, this creates a zone of torque-free shear load between the notches.
The fibers must lie parallel or perpendicular to the loading axis.
Strain gages are placed at less than 45° in the direction of the shear plane in order to determine the shear extension.
Results are shear response, 0.2% offset stress, max. shear stress and secant shear modulus.