Volume 16, Issue 5 (September 1988)
Effects of Testing Variables on Damping and Stiffness of Nailed Wood-to-Sheathing Joints
Specifications for experimental evaluation of nail-joint properties under dynamic and pseudodynamic loading are lacking. Because testing conditions affect joint properties, nailed joints between wood and plywood and between wood and gypsum wallboard were tested to determine the effect of the following factors on experimental damping and stiffness: specimen assembly technique, magnitude and rate of loading, and assumption of linear behavior in evaluating slip work. Nailing techniques controlled friction between contact surfaces, which in turn controlled damping and stiffness. Increasing loading rate increased damping and stiffness, but increasing load magnitude diminished both properties. Damping ratios were significantly lower when evaluation of equivalent viscous damping was based on linear, rather than nonlinear, behavior. Standard testing techniques are needed to achieve uniformity in dynamic testing of mechanically connected joints between structural wood materials.