TRESTLE


A 'trestle' is a bridge that consists of a number of short spans, supported by splayed vertical elements and is usually for railroad use. Timber trestles were extensively used in the nineteenth century in mountainous areas and to traverse floodplains adjacent to rivers as approaches to bridges. These were typically constructed using peeled logs preserved with creosote as vertical elements and with bolted and spiked sawn timbers for bracing.
A classic wood trestle using logs and beams

A Steel trestle with plate girder spans and steel towers

Twentieth century construction eliminated much of the need for trestles by using far more extensive grading and tunneling. The steel trestle shown to the left is a modern structure with a long expected lifetime compared to a wooden trestle. Being fire resistant in this brushy location is also an advantage.
One of the longest trestle spans created was for railroad traffic crossing the Great Salt Lake on the Lucin Cutoff in Utah. It was replaced by a fill causeway in the 1960s, and is now being salvaged for its timber.

Contents
See also

See also



Truss

Truss bridge

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