Influence of semi-rigidity of joints on the behaviour of timber structures

Abstract

The review starts by identifying the conditions for taking account of the semi-rigid behaviour of joints with dowel-type fasteners, i.e. well-defined load–displacement behaviour, no initial slip and reliable ductility. It is described how reinforcing a wood member perpendicular to the grain with fibre fabrics, plywood or densified veneer wood ensures that joints have reliable ductile behaviour. New types of fastener with desirable properties are described; with the expanded tube fastener being especially interesting. Modelling the load–displacement curves for single fasteners and joints with multiple fasteners is discussed. The so-called Plane Group of Mechanical Fasteners Model is most appropriate. The Spring Model is less suited to timber than steel. Some examples show how the semi-rigidity in the joints influences the behaviour of structural systems. The conclusions are that taking semi-rigidity of joints into account can lead to more efficient and economical structures.