G12 represents which material property in a laminate?

G12 represents which material property in a laminate?

• A. In-plane shear modulus
• B. Out-of-plane shear modulus
• C. Young's modulus in the thickness direction
• D. Poisson's ratio

Answer: (A)

G12 is the in-plane shear modulus of the lamina. It measures how the material resists shear deformation within the plane defined by the 1 and 2 material axes, and in the classical laminate theory the in-plane shear response is captured by the stiffness term Q66, which equals G12 for an orthotropic lamina. This is the property that governs tau12 in relation to the in-plane shear strain gamma12. It’s distinct from out-of-plane shear moduli (which would involve sh ea through the thickness), from the normal stiffnesses E1, E2 (and E3 through the thickness), and from Poisson’s ratio nu12, which links transverse strain to axial stress.

G12 is the in-plane shear modulus of the lamina. It measures how the material resists shear deformation within the plane defined by the 1 and 2 material axes, and in the classical laminate theory the in-plane shear response is captured by the stiffness term Q66, which equals G12 for an orthotropic lamina. This is the property that governs tau12 in relation to the in-plane shear strain gamma12. It’s distinct from out-of-plane shear moduli (which would involve sh ea through the thickness), from the normal stiffnesses E1, E2 (and E3 through the thickness), and from Poisson’s ratio nu12, which links transverse strain to axial stress.