Bond Strength of Glued-in Rods in Malaysian Tropical Timber as Influenced by Adhesive, Diameter and Glueline Thickness

Bonded-in rods are used to connect timber members, and they have been shown to be more effective than using traditional bolting methods such as nails and screws (Joseph 1999). This type of connection has been used in timber construction for over 30 years in Europe and North America for joining and anchoring glulam members, for rock anchors, for holding down bolts in concrete (Lee et al. 1981), and as rods to secure wooden turbine blades (Riberholt & Spoer 1983). Bonded-in rods are also used in timber building repairs, and to strengthen the timber (Mettem & Davis 1996). The connection is made by using high strength resins to produce a concealed timber connection. Bonded-in joints using rods are known to offer improvements by reducing weight and end-splitting, eliminating very stiff connections when loaded in an axial direction, providing greater fire resistance, and also producing a neater appearance. A good compilation of existing knowledge, including lists of basic literature, can be found in the Proceedings, PRO 22 of the 2001 RILEM Symposium on “Joints in Timber Structures”, and in the Proceedings of the CIB W18Meetings No. 28, 32, 33 and 34.