Dowel Type Joints of Round Timber Exposed to Static and Cyclic Tension Forces

Timber constructions made of round timber are becoming increasingly popular nowadays. They concern both non-pedestrian and pedestrian bridges, watchtowers and playground equipment. If these constructions are designed with a truss supporting system, the element joints are often made of bolts with slotted-in steel plates. Joints in round timber do not have sufficient support in existing Eurocodes. The problem is also in the characterization of cyclically loaded round timber joints (fatigue loading in wood). The aim of this paper is to present the results of static and dynamic tensile tests of round timber bolted joints with slotted – in steel plates along the grains. Some of these round timber joints samples were reinforced in the timber part (near the bolt) with different components (screws, special washers, steel bands, performed steel plates and nails). The main reason of the reinforcing of the joints was to increase the carrying capacity and safety of these joints in tension. Based on the results of static and dynamic round timber bolted joints tests, reinforcement of the bolted joints significantly increased joint carrying capacity and reliability.