Bath’s destructor bridge opens

Designed by Flint & Neill (rebranded as COWI on 1 January 2017) and Knight Architects and constructed by Britannia Construction, Bath’s destructor bridge connects the revitalised area of Bath Western Riverside with the A4 Upper Bristol Road over the River Avon. 

The bridge forms part of Crest Nicholson’s Bath Riverside residential development and was jointly commissioned by Crest Nicholson and Bath and North East Somerset Council. The new structure replaces a truss bridge built almost 150 years ago, which was no longer able to serve the needs of the community, nor was it capable of carrying modern traffic loads. The Victorian structure was dismantled in April last year with the replacement bridge moving into position last summer.

The new structure is an elegant 48m long asymmetric steel tied arch bridge with two box girders. It will accommodate a two-lane highway for vehicles, a wider pedestrian walkway, and a cycleway, and will provide improved access to the development area. The steel arch supports a composite deck through flat plate hangers. The prefabricated units were welded on-site in 24 pieces.

The 400 tonne bridge was launched across the river earlier this year, in a complex operation involving a self-propelled modular transporter driving the bridge from the rear, while the front end was supported by rollers on temporary towers.

The bridge has been opened to pedestrian and cycle traffic and will open to vehicles later in 2017.

Ian Firth, project director at Flint & Neill commented: “The design incorporates a single eccentric arch due to the proximity of the building soon to be built at the south east corner of the bridge, and this generated some interesting engineering challenges in the design. There is a wide box girder under the west side which works together with the arch to resist the tendency for the bridge to twist with traffic load on one side only. This unusual arrangement demanded careful treatment in the design, but we have been able to keep the bridge looking very slender, with the clean elegant lines desired by the architects.”

Sam White, senior designer at Knight Architects said: “The City of Bath is a globally renowned UNESCO world heritage site. This was a unique opportunity to build its first new crossing of the River Avon in the city centre for over 100 years and one which we hope will be both a new landmark for the Bath Western Riverside development and a destination for people using the river corridor.”