Mechanical Performance of Toothed Metal-Plate Connected Glubam Joints

Abstract

Toothed metal-plate connector (MPC) is a cost-effective connection method, easy to install with high assembly efficiency for manufacturing engineered timber trusses. In this study, In order to combine the advantages of the MPC with glued laminated bamboo (glubam) structures, a total of 136 MPC glubam joints, divided into 22 groups according to testing parameters, were tested and analyzed. Design strength values of the anchorage strength of metal plate tooth embedded in glubam, the tensile and shear strengths of toothed metal plate in glubam joints were provided in reference of the existing timber code specifications. The results show that the linear interpolation formula provided by the existing design code largely overestimates the anchorage strength of metal plate tooth embedded in glubam for the nonorthogonal loading directions. An angular equation expressed as the loading direction is therefore proposed. The design shear strength of aligning the major axis (tooth slot direction) of the metal plate parallel to the plate longitudinal direction is higher than that of aligning plate major axis perpendicular to the plate longitudinal direction, especially for the combined shear and tension loading. The design tensile and shear strengths of the MPC glubam joints are obviously larger than those of the Class I MPC timber joints given in the Chinese Standard, indicating that the MPC glubam is hopeful to be alternative to replace the MPC timber structures such as roof truss systems.