Experimental Testing and Analytical Modeling of Glulam Moment Connections with Self-Drilling Dowels

Abstract

An experimental and analytical study on rotational behavior of glulam beam-column moment connections with self-drilling dowels (SDDs) is conducted. Connection properties including strength, stiffness, ductility, and energy dissipation were experimentally evaluated by testing seven full-scale connection specimens with and without self-tapping screw (STS) reinforcement along timber perpendicular to grain. All the connections showed high initial stiffness and high moment capacity when compared with the test results of bolted connections reported in the literature. The unreinforced connections had relatively low ductility due to timber splitting despite the increased fastener edge distance. The STS reinforcement effectively reduced the timber splitting tendency and encouraged the yielding of more SDDs, leading to slightly increased moment capacity, but significantly improved ductility. A modified analytical model (MAM) is then proposed to predict strength and rotation of the SDD moment connections based on force and moment equilibrium of the glulam members. Improved prediction accuracy is achieved for the SDD moment connections when compared with the past analytical methods.