Abstract
Shearing tests were carried out on mechanical timber joints composed of a main timber and two thick particleboards (side members). Six kinds of commercial screws or nails were used for mechanical fasteners. Maximum load, allowable load, stiffness and dissipated energy of the joints were calculated from load-deformation curve. Short term allowable shear strength calculated with an equation in “Standard for structural design of timber structure” was about one-third of measured maximum load. Estimated yield load with “European Yield Theory” was lower than measured yield load. Effects of shapes of fasteners on the mechanical characteristics were examined with linear or multiple regression analysis. The regression formula using the shape of the fasteners and the density of the main member as independent variables estimated each characteristic value properly. The shape of the fasteners affecting each characteristic value agreed well with classification results by principal component analysis. Stiffness of the joints was not affected with the shape of the fasteners or the density of the main member. Bending strength of the particleboard did not affect on the mechanical properties of the joints.
