New estimation method on stiffness and strength of single-shearing screw joints with structural panels

Abstract

Screws are commonly used for timber constructions. Especially, single shearing characteristics of screw joints with structural panels are important. New estimating equations on initial stiffness, yield strength, secondary stiffness, and ultimate strength of single shearing screw joints were proposed. To confirm validity of the hypothesis, load-slip curves on a series of single shearing test were measured. The simple estimating equations of initial stiffness under considering a fastener as rigid-body were applicable enough by defining "effective rigid-body length." The yield strength was evaluated as the sum of yield strength by European Yield Theory and friction caused by initial axial force of the fastener. The secondary stiffness could estimate by using axial force. But in some series, the estimation value was higher than the test value because a selected failure mode was different from the actual failure mode. The ultimate strength could be predicted from yield strength and axial force.