Wooden Bridges (History)
Introduction
Wooden bridges are almost certainly the oldest type of structures used to overcome terrain obstacles such as stream beds or small ravines.[1] Starting with the simple trunk of a tree placed between the two banks of a stream, wood construction evolved over the centuries giving rise to the first trusses. Since the wood has a very low specific weight, it is especially suitable for the construction of bridges. In this article a distinction is made between open and covered wooden bridges.
History
The ancient Gauls already knew about wooden bridges. They built cantilevered structures, which consisted of logs stacked at right angles completed with stone infill and connected to a wooden superstructure. The design is said to have been used in Savoy until the 19th century. Bridges made of stones and logs are still used today in Pakistan, Afghanistan, India and in some rural areas of China "China (region)") to cross rivers, mainly in the Himalayas and adjacent mountainous areas. To do this, on both banks, abutments formed with stones stacked are placed so that their ends protrude towards the center of the river, which are then connected with logs placed on top.[2].
The first important wooden bridge of Roman times was the Sublicio bridge.[3] The Romans built both completely wooden bridges and bridges with stone pillars and wooden decks, called stone pillar bridges (see Annex: Roman bridges). In completely wooden bridges, the most common design consisted of driving wooden piles into the river bed, which were connected by a wooden walkway. Another Roman wooden bridge, which is represented in the bas-reliefs of Trajan's column, is the Orșova bridge over the Danube, attributed to Apollodorus of Damascus.[4].
In the Middle Ages it is known that the master builder Villard de Honnecourt built cantilever bridges using wooden lattices.[5] However, this construction method does not seem to have spread and was only taken up in the middle of the century by Heinrich Gerber, who used it in the construction of iron lattice structures. During this time, construction also began on covered bridges, in which the supporting structure is protected from the effects of the weather by side walls and a roof. The first examples are the Kapellbrücke built in Lucerne "Lucerne (city)") in 1365 or the Ponte Vecchio "Ponte Vecchio (Bassano del Grappa)") built by Andrea Palladio in 1569, a covered bridge supported on wooden piles over the Brenta River in Bassano del Grappa.[6].