FAN-LIKE BRIDGE FOR LONDON
08 Oct 2014
An innovative design for a footbridge in London sees the ‘kinetic sculpture’ open and close like the blades of a traditional hand-held fan.
British firm Knight Architects and structural engineers AKT II have completed a moving footbridge in Paddington, London, that opens and closes like the blades of a traditional hand-held fan.
Consisting of five steel beams that rise and fall using hydraulic jacks, Merchant Square footbridge spans a 20-metre width of the Grand Union Canal in Paddington Basin, close to Thomas Heatherwick's Rolling Bridge that curls into a ball.
The architects, who specialise in bridge design, won a limited competition to design the crossing in 2012 with their plans for a "kinetic sculpture" that could rise to allow canal boats to pass along the waterway.
Opening in sequence, the bridge's five beams rise to different angles to create a fan-like effect. The first rises to 70 degrees, while the last lifts high enough to create a clearance space of two and a half metres over the surface of the canal. The weight of the beams – which range from six to seven tons – is balanced by a 40 ton counterweight that keeps the beams steady as they rise and fall.
When fully closed, the bridge is safe for pedestrians and offers a three-metre wide crossing. "Shaped counterweights assist the hydraulic mechanism and reduce the energy required to move the structure," explained the architects and engineers.
"The bridge balustrades are formed from twin rows of inclined stainless steel rods, overlapping to form a robust yet filigree and highly transparent structure."
The handrail formed by these balustrades features a built-in strip of LED lighting to illuminate the crossing at night. Like Heatherwick's bridge, the structure opens every Friday to let boats sail past.
The bridge is part of a wider regeneration project for the site, with future plans including a garden square with an events space and water maze. A total of six new buildings will be constructed, with three already complete.