Experimental and numerical studies on the mechanical properties and behaviors of a novel wood dowel reinforced dovetail joint

Abstract

To improve the mechanical strength of dovetail joints, resisting and postponing the crack propagation, a novel method of enhancing the mechanical strength of the dovetail joint using a dowel-reinforced method was proposed. The connection technical parameters of the dowel-reinforced dovetail joint (DRDJ) were investigated and optimized based on experimental and numerical methods. The results showed that there were three typical mechanical behaviors of the DRDJ characterized, and each of them can be separated into three regions, i.e., elastic region, crack propagation region, and failure region, by the defined crack initiation point and critical fracture point. The effects of dowel inserting distance and depth on mechanical properties of the DRDJ was significant. The proposed method was validated experimentally to be an efficient approach to improving the crack initiation load, critical fracture load, and elastic stiffness, and delay crack propagation. The connection technical parameters of the DRDJ were analyzed based on response surface method and experimentally validated to be the distance of 18.56 mm and depth of 32.19 mm. Tensile strength of the DRDJ was seriously influenced by wood dowel species and dowel fit, and increased with the increase of dowel fit and mechanical strength of wood dowel based on numerical analysis. In conclusion, the dowel-reinforced method is capable of improving the mechanical strength of dovetail joints, resisting and postponing the crack propagation, and has an advantage on the risk of pre-warning of wood structure failure.