Trestle support

In structural engineering, a trestle support (or simply trestle) is a structural element with rigid beams forming the equal sides of two parallel isosceles triangles, joined at their apices by a plank or beam.

In shape and manufacture, it sometimes resembles variations of the antique field desk, which were used by officers close to the battlefield.

[1] Timber and iron trestles (i.e. bridges) were extensively used in the 19th century, particularly for railroads.

Timber trestles remain common in some applications, most notably for bridge approaches crossing floodways, where earth fill would dangerously obstruct floodwater.

Many timber trestles were built in the 19th and early 20th centuries with the expectation that they would be temporary.