Over 650 new Timber bridges have been built in Sweden over the last 15 years. However, the Swedish Transport Administration's regulations for inspection of bridges are intended mainly for concrete and steel bridges. The materials used in wooden bridges are very different from those used in concrete and steel bridges. While it is corrosion that presents the greatest risk to concrete and steel bridges, it is moisture absorption by the wood, and the risk of attack by rot, that are the most important to monitor in the case of timber bridges. If the wood structures are kept dry - i.e. if the moisture content in the wood does not exceed 20 % over any longer periods - the structure can be expected to have a very long life. Regular inspections ensure that any problems are found at an early stage, thus enabling them to be dealt with in good time and proper maintenance work can be performed.
SP Wood Technology arranges training in inspection of timber bridges. The training covers the special features of timber bridges, wood materials and the particular factors concerned in inspection of wooden structures. The courses are intended for those involved in such work in the Swedish Transport Administration, local authorities, consultants and other who need to know about timber bridges and their maintenance. See 'Training' tab.
SP Wood Technology has published several reports on timber bridges, mostly in Swedish. The reports can be ordered from the publications tab.