Experimental testing of reinforced end-notched glulam beams

Abstract

Notches made at the ends of timber beams significantly decrease load carrying capacity of a structural member. This paper presents an experimental research on bending behaviour of end-notched glulam beams, with and without reinforcement. Screws for timber were used as reinforcement, positioned at angles of 90° and 45° to the longitudinal beam axis. The unreinforced beams failed due to crack opening and its propagation in a brittle manner. Cracks that appeared in the notch details resulted from combined excessive tensile stresses perpendicular to grain and shear stresses. This study shows that reinforcing the beams at the notched ends can improve their load carrying capacity and deformability. However, applied screws did not help the beams achieve ductile failure in bending. The shear failure was dominant failure mechanism for reinforced beams. In addition, analytical calculations were performed in accordance with Eurocode 5 so as to compare the results with experimental research.