Small Bending Stiffness Research Articles

A method of measuring the shear modulus of thin xylonite sheet

A torsion balance is described, in which a common torque is applied to narrow strips of steel and xylonite connected end to end, and the twist of each specimen is measured. Knowing the shear modulus of steel, its twist gives a measure of the torque, and the shear modulus of the xylonite may then be calculated from its rotation. The measurements throughout are very easily made, and they do not depend in any way on frictional forces, nor are any forces applied to the specimens apart from the end forces producing the torque. These features are particularly important for thin xylonite which has very small torsional and bending stiffness.