Gantry (road sign)

For other uses, see Gantry (disambiguation).
A gantry on the Cherokee Turnpike in Northeast Oklahoma
A gantry of British semaphore signals seen from the cab of a steam locomotive

A gantry (also known as a sign holder, road sign holder, sign structure or road sign structure) is a traffic sign assembly in which signs are mounted on an overhead support, or railway signals supported.

Gantries are usually built on high-traffic roads or routes with several lanes, where signs posted on the side of the highway would be hard for drivers to see. Gantries may be cantilevered or one sided on the left, right and center (sometimes referred to as a half-gantry or Butterfly gantry), or they may be bridges with poles on each side. Similar gantries are used in railway signalling on multi-track lines.

Around the world

Canada

Gantry signs are commonly used in urban highways in Canada to support overhead signs. Half-gantries are used to place signs near exits where space does not permit having signs to the right side of the roadway. Gantries can also be used to hold cameras for toll road entrances/exits and to hold electronic information signs such as on Ontario Highway 407. The style of gantry used are mostly truss gantries. Older gantries have truss supports (round or box) and newer ones are now supported by cylindrical legs.

Hong Kong

Hong Kong's highways use a Gantry crane type to support signs. The road signs are usually located on top and some have lights to indicate open or closed lanes.

United Kingdom

Gantry signs are being installed at various locations around the trunk motorway network as increasing amounts of traffic mean that road signs at the side of the carriageway are frequently obscured by large goods vehicles. They may also consist of variable-message signs, and more recently Active Traffic Management, to close lanes due to accidents and for other reasons. They can also be used to specify temporary speed limits. Gantries in the United Kingdom display exit (junction) numbers, distances to junctions / exits (1 mile, 1/2 mile, 1/4 mile, 1/3 mile, 3/4 mile, 2/3 mile) and destinations reached, and if necessary what lane to use for them.

United States

A tubular piped gantry in California.

Gantry signs are used frequently in the U.S., particularly in urban areas where freeways have an exit every mile to fit in with the grid system. These half-gantries usually have the exit number and the road or street that can be reached. Gantries can also span the whole road, such as at major junctions.

Designs

See also

This article is issued from Wikipedia - version of the 9/5/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.