Glued threaded rods are among the most powerful connectors in modern timber construction engineering. Whether they are glued in parallel or perpendicular to the grain direction, powerful forces can be applied in small areas of wooden components. In conjunction with Professor Ernst Gehri, neue Holzbau AG (n’H) has been conducting research in this area since the late 1990s. Under the brand name ‘GSA®-Technology’, a range of solutions has since been developed that are being successfully applied in various timber frameworks all over the world.
Wood, resin and steel form an interlocking system, requiring the harmonisation of all three components’ properties. Certain rules and conditions must be complied with if optimum connections are to be created. To avoid any brittle fracture modes of either the wood or the adhesive, connections must be designed so that it is the steel rods (ductile) that fracture in a state of failure.