October 13 2014 – Wired
For most of the week, the new Merchant Square Footbridge in London does what we expect of a bridge: It helps people get from one place to another. But a truly great bridge adds to the character of its environment, and the Merchant Square Footbridge does that, too. Every Friday afternoon, it heaves open like a 60-foot-tall Japanese hand fan.
The bridge was designed by Knight Architects, a London firm specializing in bridges, in collaboration with structural engineers AKT II. It spans the Grand Union Canal in Paddington Basin, near a public space called Sunset Terrace. The brief called for a bridge with eight feet of clearance, so boats could pass into the basin beyond, but also one that could serve as a “focal point” for the area. In a write-up of the project, the architects explained their thinking: “We considered that movement in the horizontal plane would not be interesting— no more so than a 20 meter narrowboat turning in the canal—but in contrast, how much more exciting it would be if a 20 meter narrowboat were raised upright!”
Bridge building is always a compromise between engineering and architecture, and here that meant achieving the spectacular effect as practically as possible. For its final design, Knight split the 10-foot-wide walkway into five steel fingers. Hydraulic jacks lift individual beams into the air, with shaped counterweights—40 tons in all—reducing the energy needed to lift them. The highest finger points skyward at a 70 degree angle. As Bartlomiej Halaczek, one of the architects on the project, explained in an interview, the design provided the “visual drama” everyone wanted without adding significantly to construction costs or bridge upkeep.
The bridge isn’t the first in the neighborhood to double as kinetic sculpture. Thomas Heatherwick’s well-known roly-poly bridge is just around the corner. Both are arresting examples of the architectural possibilities of bridges, something Martin Knight, head of Knight Architects, touched on in a talk earlier this year. Bridges, he suggested, “can be understood as sculpture with a clear purpose, an accessible form of art where the load-carrying system can be readily comprehended and opinions can be formed with a degree of confidence many people find lacking when viewing high art.”
It’s something of a radical notion—that bridges, by virtue of their humble infrastructural obligations, can serve as Trojan horses for getting people to think about art and architecture and the built environment in novel ways. That isn’t to say the architecture of bridge-building is more important than the engineering. A bridge that delights and inspires art art is of little value if it isn’t also effective and economical as infrastructure. Knight reached the same conclusion in his talk when he said, “Ultimately, in the design of bridges, the best design will satisfy both artistic and scientific analysis.”