Date of Graduation
Davis College of Agriculture, Natural Resources and Design
Wood Science and Technology
Elemer M. Lang.
Wood is prone to deterioration that reduces its load bearing capabilities. Periodically, older wooden members need to be inspected to ensure the strength and stability of the structure. Historically these inspection methods have consisted of visual inspections lacking scientific basis.;Non-destructive testing (NDT) methods were investigated by this research for the possibility of evaluating modulus of rupture and modulus of elasticity of built-in wooden members. Methods included stress wave timing for dynamic MOE determination and screw withdrawal force (SWF) for MOR and density prediction. Standard ASTM testing procedures were used to determine the actual properties and statistical relationships between these variables identified. Using the developed relationships, simple prediction models were developed to estimate actual properties.;Results of this investigation revealed that stress wave timing is a reliable predictor of the actual MOE of the material. Investigation results also indicated that SWF is a reliable indicator of both density and MOR.
Gray, Jody D., "In situ determination of strength and stiffness of structural lumber and composite products" (2003). Graduate Theses, Dissertations, and Problem Reports. 1321.