Rigid connections in structural timber assemblies

Bonded-in rod joints have several advantages over the conventional type of joints in terms of performance, cost and aesthetics. The use of basalt fibre reinforced polymer (BFRP) rods would result in lower weight of the joint and improved resistance to corrosion but there appears to be little or no investigation on the use of these rods in the bonded-in rod technique. The aim of this research was to examine the behaviour of bonded-in BFRP and steel rods and to propose design models to enhance current knowledge in bonded-in rod technology. The mechanical properties of the timber members were characterised so as to predict the behaviour of donor and spliced beams for the proposed stressed model. Pull-out tests of the rods were conducted to investigate some factors that affect joint capacity and based of the results bonded-in rod timber beams were fabricated and tested for ultimate capacity and flexural stiffness. An analytical model based on the interfacial tress-strain interaction of the BFRP rods with the adhesive layer and the timber members was developed to predict pull-out capacity of the samples. Average shear strength from steel pull-out tests was also used to propose a design equation for pull-out capacity of steel samples. In both the BFRP and steel samples, good agreement with the tests results was observed. A trapezoidal timber compressive stress model was developed to predict ultimate moment capacities of steel and BFRP timber beams. Good agreement was found between the theoretical and bonded-in steel rod beams whereas results form bonded-in BFRP rod beams were lower due to tensile splitting. Bonded-in steel beams recorded higher stiffness than the theoretical stiffness, whereas there was strong agreement between the theoretical predictions and BFRP beam tests. Thus, the presented models may serve as a useful reference for future design of bonded- in rod joints.EThOS - Electronic Theses Online ServiceGBUnited Kingdo