Trestle
Trestles are useful as approaches to bridges over marshes and shallows
Ancestor:	Beam bridge, clapper bridge
Related:	None
Descendant:	Viaduct
Carries:	Heavy rail
Span range:	Short
Material:	Timber, iron, steel, reinforced concrete, prestressed concrete
Movable:	No
Design effort:	low
Falsework required:	No

A trestle is a bridge that consists of a number of short spans, supported by splayed vertical elements and is usually for railroad use. A Beam Bridge is a direct descendant of the Log bridge, now more normally made from shallow steel 'I' beams, box girders, A A viaduct is a Bridge composed of several small spans The term viaduct is derived from the Latin via for road and ducere to Lumber or timber is Wood in any of its stages from felling through readiness for use as structural Material for Construction, or Iron (ˈаɪɚn is a Chemical element with the symbol Fe (ferrum and Atomic number 26 Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 Reinforced concrete is Concrete in which reinforcement bars (" Rebars quot or fibers have been incorporated to strengthen a material that would otherwise be Prestressed concrete is a method for overcoming the Concrete 's natural weakness in tension. Falsework consists of temporary structures used in Construction to support spanning or arched structures in order to hold the component in place until its construction is sufficiently A bridge is a Structure built to span a Gorge, Valley, Road, railroad track, River, Body of water Timber trestles were extensively used in the nineteenth century in mountainous areas and to traverse floodplains adjacent to rivers as approaches to bridges. ||-||-||-||-||-||-||-||}A floodplain, or flood plain, is flat or nearly flat land adjacent to a Stream or River that experiences occasional or periodic A bridge is a Structure built to span a Gorge, Valley, Road, railroad track, River, Body of water These were typically constructed using peeled logs preserved with creosote as vertical elements and with bolted and spiked sawn timbers for bracing. Creosote is the name used for a variety of products including wood creosote and coal tar creosote.

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. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 In many parts of Australia, trestle bridges were replaced with earth-fill over corrugated iron pipe culverts. A culvert is a conduit used to enclose a flowing body of Water.

The steel trestle shown below (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. Great Salt Lake, located in the northern part of the US state of Utah, is the largest salt lake in the western hemisphere the fourth-largest terminal The Lucin Cutoff was a Railroad Trestle which crossed the Great Salt Lake in Utah. The State of Utah (ˈjuːtɔː or) is a western state of the United States. It was replaced by a fill causeway in the 1960s, and is now being salvaged for its timber. In modern usage a causeway is a road or railway elevated by a bank usually across a broad Body of water or Wetland. The 1960s decade refers to the years from the beginning of 1960 to the end of 1969

Many wooden roller coasters are built using design details similar to trestle bridges because it is so easy to make the roller coaster very high . The roller coaster is a popular Amusement ride developed for Amusement parks and modern Theme parks LaMarcus Adna Thompson patented the first Since loads are well distributed through large portions of the structure it is also resilient to the stresses imposed. The structure also naturally leads to a certain redundancy (provided that economic considerations are not overly dominant). Such wooden coasters, while limited in their path (not supporting loops), possess a certain ride character (owing to structural response) that is appreciated by fans of the type.

See also