Shear Strength of Wood Beams: A Weibull Analysis

A size-strength relationship for the shear strength of Douglas fir beams has been developed using Weibull's statistical theory of strength of materials. The two-parameter statistical model has been found sufficient for experimental data analysis. Arbitrary loading conditions as well as bearing sizes are considered in the present study. Numerical results indicate that the existing shear strength data obtained from the ASTM shear block tests coupled with the present analysis can serve as a simple, yet reliable, design criterion for the practicing engineer. Design procedures are illustrated by numerical examples.