Trestle Bridge
Trestle (English: scaffolding ) or trestle bridge or scaffolding pillar viaduct is a type of bridge made of load-bearing elements with a short span that lie on scaffold-like supports (trestles) that taper upwards . It is most commonly used as a railway bridge .
Trestle bridges are made of prefabricated wooden or steel beams. Railings or parapets are usually not used on these bridges.
Trestle bridges were originally built of wood in the United States. The problem turned out to be that the steam locomotives used at the time occasionally emitted sparks that could set these wooden bridges on fire . Among other things, the Portageville Viaduct burned down in 1875 ; it was replaced by a steel structure. With the switch to diesel locomotives , this problem was eliminated; Wooden bridges were also often destroyed by arson ; therefore the steel construction prevailed. A few wooden trestles still exist in America, such as the Goat Canyon Trestle in California .
In Germany, trestle bridges were built for some branch lines in central Germany. For example the Ziemestal bridge on the Triptis – Marxgrün railway line in Thuringia. In Austria they are only available on the Ybbstalbahn mountain route in Lower Austria and the Stubaitalbahn in Tyrol.
In 1901 a 180 m long and 32 m high Trestle Bridge was built in the English county of West Yorkshire in order to operate a 9 km long narrow-gauge railway line to dam construction sites. The bridge was auctioned and dismantled in 1912.
In the 1930s the scraper was invented; he made the heaping of railway embankments cheaper. Instead of trestle bridges, embankments have now been built in many places. If flood-prone floodplains need to be crossed, embankments are not an option, however.
