Transporter of delight - design of footbridge in the Docklands district of London

Architectural Review, The, May, 1999 by Catherine Slessor

This footbridge in London's Docklands explores nautical forms and materials to create a striking new landmark.

Dating back to the era of robust and inventive Victorian engineering, the transporter bridge is not a new idea. The notion of ferrying people and vehicles across water in a moving platform or gondola slung from a gantry-like structure was first proposed by an English engineer Charles Smith in 1873 and later evolved by his French counterpart Ferdinand Arnodin in the early twentieth century. Adopted for deep water crossings, where the frequent passage of shipping might compromise a conventional opening bridge, transporter bridges are a dominant feature of industrial port skylines from Middlesbrough to Bilbao.

For this new footbridge in London's Docklands, Lifschutz Davidson (working with structural engineer Techniker) reinterpret the principles of the transporter bridge to create an elegant, lightweight structure that has become a new landmark for the area. Spanning Royal Victoria Dock in the bleak and still relatively ungentrified eastern fringe of Docklands (near the small City airport), the new bridge was the outcome of a competition held in 1996. The vast basin of Royal Victoria Dock is currently being converted into a regional sailing centre and the competition brief called for a new enclosed footbridge with appropriate clearance for sailing craft and a low profile to reduce wind turbulence. Taken literally, this suggested an uninspiring tube-like structure, sealing pedestrians off from the outside world, so Lifschutz Davidson proposed the alternative of an open bridge with an enclosed gondola slung beneath it. Due for installation in the second phase of the bridge's development, the glazed cabin (which can hold up to 40 people) will be hung from the underside of the bridge deck structure. An adjustable suspension cable mechanism enables the gondola to be raised from the quayside landing stations to deck level and propelled over the dock like a monorail. Alternatively, it can skim lightly across just above the water when there are no boats in the vicinity.

The broad promenade of the pedestrian bridge gives spectacular views over the docks, but as it is uncovered, its use will depend to some extent on the clemency of the weather. Embodying a tough aerodynamic spirit, the tall masted structure of the bridge deck is inspired by the dock landscape of gaunt cranes, masts and cables. Poised 15m above the water, the bridge structure takes the form of a steel Fink truss spanning 130m and supported at each end by a pair of trestles. Five box girder beams make up the Fink truss. This particular structural form was selected for its capacity to combine lightness of construction with very long spans. Six tapering conical steel masts of varying lengths are linked by cables to tie-down points along the length of the deck. At each end of the bridge, another cable carries tension forces to the ground through an angular bowsprit adding to the dynamism of the overall composition.

Materials have a functional, maritime rigour - the steel structure is partnered with a hardwood deck and handrails, and perforated stainless-steel cladding panels enclose the stair and lift towers. At night, the bridge is magically illuminated, emphasizing the sleek profile of the structure. Downlighters pick out the tall cable masts while concealed fittings on the balustrades and soffits diffuse shafts of light through the timber decking to illuminate the skeletal whalebone structure of the box beam. Over the years, Lifschutz Davidson have developed an admirable record of decent, modern buildings that both respect and revive their surroundings (for example the remodelling of the Oxo Tower, AR February 1997). This latest project adds to their reputation.

Architect Lifschutz Davidson, London

Structural engineer Techniker

Mechanical and electrical engineer Allott & Lomax

Cost consultant Davis Langdon & Everest

Fire engineer FISEC

Lighting consultant Equation

Photographs 1, 3 Chris Gascoigne 2 Marcus Robinson