What does short-beam shear testing measure?

What does short-beam shear testing measure?

• A. Interlaminar shear strength by applying three-point bending to a short beam and observing failure.
• B. In-plane shear modulus.
• C. Out-of-plane bending stiffness.
• D. Fiber tensile strength.

Answer: (A)

Short-beam shear testing assesses the interlaminar shear strength of a laminated composite. In this test, a short beam is loaded in a three-point bending setup. Because the beam is short, the bending causes concentrated shear between the adjacent plies near the midspan, so the failure typically occurs along the interfaces between layers. The load at failure is used to determine the interlaminar shear strength, which characterizes how well the laminae resist sliding past one another. This test does not measure in-plane shear modulus, which would require tests that apply shear within the plane of the laminate; nor does it measure out-of-plane bending stiffness, which relates to how a laminate resists bending as a plate; nor does it measure fiber tensile strength, which is obtained from tension tests along the fiber direction.

Short-beam shear testing assesses the interlaminar shear strength of a laminated composite. In this test, a short beam is loaded in a three-point bending setup. Because the beam is short, the bending causes concentrated shear between the adjacent plies near the midspan, so the failure typically occurs along the interfaces between layers. The load at failure is used to determine the interlaminar shear strength, which characterizes how well the laminae resist sliding past one another.

This test does not measure in-plane shear modulus, which would require tests that apply shear within the plane of the laminate; nor does it measure out-of-plane bending stiffness, which relates to how a laminate resists bending as a plate; nor does it measure fiber tensile strength, which is obtained from tension tests along the fiber direction.