Merchants Bridge, Bridgewater, Castlefield
1995
Castlefield was at the hub of canal and rail communications supplying raw materials such as coal to help fuel Manchester’s Industrial 'Revolution’ of the 18th and 19th centuries. Manchester City Council designated Castlefield a conservation area in 1979 and the area became Britain’s first urban heritage park in 1982.
Merchants Bridge
Regeneration of the Castlefield area necessitated building a 67 in long footbridge to link the new Slate Wharf on the southwest side of the Bridgewater Canal wit the old Catalan Square, on the northeast side. A design competition for this bridge, Merchants Bridge, stipulated a striking structure which would offer the best of 20th century design and engineering while complementing the seven established bridges at the site which cover 200 years of history.
Bridge Concept and Design
Consulting engineers Whitby & Bird won the competition with a tubular steel design which demonstrated technological advance but used a curving form to empathise with the established bridges. Architectural and engineering criteria were met with a sickle arch solution in which deck and support arch curve in opposite directions, each balancing and reacting with the other. This solution confers greater resistance to the bridge deck in resisting out-of-plane loads. Vertical loads on the deck are transmitted into the plane of the arch by the horizontal stiffness of the deck, and the arms acting as ties. The arch is restrained against buckling by the torsional stiffness of the aerofoil deck. The 85 tonne structure was designed principally in CHS and plate
Fact file
Client
Central Manchester Development Corporation
Architect
RHWL Partnership
Main Contractor
The Angle Ring Co Limited
Structural Engineer
Whitby & Bird
Steelwork Contractor
Watson Steel Limited
