The Solid-Rod Torsion Test for the Determination of Unidirectional Composite Shear Properties

The primary requirements of a desirable shear test method include the ability to introduce a well-defined state of stress in the specimen, capability of determining both shear modulus and shear strength with one test of a single specimen, use of a minimum amount of material per specimen, ease of specimen fabrication and preparation, and simplicity of testing. The solid-rod torsion test is shown to fulfill these requirements. Methods and equipment developed for both the fabrication and testing of specimens are discussed in detail. Experimental data obtained by utilizing the solid-rod torsion test on several different, composite-material systems are presented. These results are then compared with data obtained by utilizing other shear-property test methods.