Sign gantries, consisting of prestressed beams and reinforced columns, are currently being used on motorways and major roads. Depending on the cross-section of the beam used, spans of up to 41 metres can be achieved; sufficient for spanning across both carriageways of a motorway. Units offer fast and economic erection, which is particularly advantageous when being installed on ‘live’ roads. Columns are placed in preformed sockets in the foundations and can be designed to be demountable for reuse elsewhere. Beams are provided with the necessary fixings for the signs already cast in.
The following benefits are afforded to the public, highway authority and construction team by the ability of concrete gantries to eliminate central reserve support legs:
- Removes the need for extensive traffic management schemes on live roads.
- Contains construction work for gantry legs to the hard shoulder.
- Reduces traffic disruption during construction.
- Improves workforce and public safety.
- Reduces cost of maintenance and associated traffic disruption.