Determination of dynamic shear modulus of structural adhesives in thick adherend shear test specimens

The viability of using the thick-adherend shear test (TAST) specimen to find the dynamic shear modulus of structural adhesives has been studied. Two different modes of vibratory deformation have been considered. In both cases, it has been shown that, in practical situations, simple vibratory models are inadequate for representing the modal vibration of TAST specimens. Expressions based on empirical results have been presented, and it has been shown that such expressions can adequately yield the adhesive shear modulus from dynamic tests. Experimental verification has been carried out using a number of different adhesives. The tests are nondestructive and the specimens may then be subjected to the normal quasi-static loading to fracture.