Reinforcement of timber beams

High performing, such as highly loaded, and large span timber beams are often used for sports and industry halls, public buildings or bridges, and provide an aesthetically pleasing and environmentally friendly structural solution. Reinforcement of beams may be required to extend the life of the structure due to deterioration or damage to the material or due to a change of use. The main aim of this chapter is to summarise the current and emerging methods that are available to repair or enhance the structural performance of timber beams. An overview of the main materials, cross sections and geometries used for timber beam structures is presented. Furthermore, their general failure modes are described and typical reinforcement methods and corresponding retrofitting techniques are given. For each of the failure modes, the methods and their advantages are summarized. The reinforcement methods include wood to wood replacements, use of mechanical fasteners such as screws and rods, and methods which add additional strengthening materials.