British designer Thomas Heatherwick may now be best known for his crazy expensive and controversial bridge proposed for the Thames in London, but he has been building bridges for a while. In New York City, an exhibition of his work is on display at the Cooper Hewitt, in the show Provocations: The Architecture and Design of Heatherwick Studio. Some of the bridges on display, built and unbuilt, are technically amazing and very beautiful.
Rolling Bridge 2004
The aim was to make the movement the extraordinary aspect of the bridge. A common approach to designing opening bridges is to have a single rigid element that fractures and lifts out of the way. Rolling Bridge opens by slowly and smoothly curling until it transforms from a conventional, straight bridge, into a circular sculpture which sits on the bank of the canal. The structure opens using a series of hydraulic rams integrated into the balustrade. As it curls, each of its eight segments simultaneously lifts, causing it to roll until the two ends touch and form a circle. The bridge can be stopped at any point along its journey.
Watch the video:
Large span rolling bridge, 2009
Now he has a much larger rolling bridge in the works, big enough to cross the Thames.
Simpler than its predecessor, Large Span Rolling Bridge would use cables, gravity, and an electric winch to fold decks into each other to open the bridge. On this model, a handle operates a winch that pulls cables synchronized by a system of pulleys.
Glass Bridge 2003
Heatherwick doesn't limit himself to the traditional materials either; here he tries to build a bridge out of glass. And not just the floor of the bridge, which has been done often; here, it's the entire structure.
To celebrate the luminous potential of glass and use it as a sole structural material, the studio experimented with compressing 1,200 pieces, or 154 tons, into a traversable beam. Bridges have been built using compression since the stone arches of antiquity; this new design squeezes sheets of industrially produced flat glass horizontally.
Look at how this works: 1100 tonnes working a lever that presses the glass together. Bridges may have been built with compression forever, but not like this. "A test with full-size rigs proved that the glass beam was strong enough to support a person standing at its midpoint."
Jiading Bridge 2013
However the one that excited me the most was this modern interpretation of a traditional Chinese moon bridge.
The traditional bridges are actually hard to climb, and not accessible to those in wheelchairs. Heatherwick has designed one where each step slides up and down so that it can flatten out.
The studio adapted the elegant S-curves of historical Chinese moon bridges to design a 65-foot-long waterway span for the Shanghai satellite town of Jiading. The hydraulic-powered bridge is constructed from threaded C-shaped sections: they flatten for wheelchairs and rear up into a hump, with pedestrian stairs, for passing boats underneath.
Unlike a conventional drawbridge, this bridge is crossable in any position — up, down, or in between. The contrasting materials of the sections— exterior machined steel and interior bronze —visually accentuate the bridge’s transformative movement.
That's totally amazing.
Pedestrian bridges are a different experience than those that one drives over; you take them slowly, and really have the time to admire the design and the engineering. And it's rare to see such major civic investments in pedestrian infrastructure. Heatherwick pushes the envelope to a new level of interest. See all of the exhibition at the Cooper Hewitt in New York City, open until January 3.