Load-Slip Characteristics of Metal Plate Connected Wood Joints Tested in Tension and Shear
Keywords:Load-slip, metal plate, wood joint, stiffness, strength, modeling
Thirty-six metal plate connected wood joints were tested in tension and shear to failure to determine their strength and stiffness characteristics and failure modes. Twenty-one of the joints were tested in tension, and the rest were tested in shear. Test specimens included the four Canadian standard orientations and intermediate orientations of 30, 45, and 60°. For the joints tested in tension, failure was by plate shear for the 0°, by tooth withdrawal for the 30 and 45°, and by wood failure for the 60 and 90° orientations. For the joints tested in shear, failure was consistently by tooth withdrawal for the 0, 30, and 45°, and by plate shear for the 60 and 90° orientations.
A 2-parameter nonlinear model characterized the P-Δ curve quite well. When characterizing the P-Δ curve, the entire curve extending from zero to the ultimate load was used. The stiffness values for the intermediate angles were calculated from the stiffness values of the standard orientations using a Hankinson-type formula.
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