This Bridge Opens and Closes Like a Japanese Folding Fan

In an engineering first, architects designed the slats of the fabricated steel span into a cascade of cantilevers

Join Our Community of Science Lovers!

Inspired by a Japanese folding fan, Merchant Square Footbridge in Paddington, London, gracefully opens above a historical canal at least once a week to allow small boats to pass. It was completed last year, and its unique design is a 2015 finalist for a prestigious award from the Institution of Structural Engineers. The organization annually honors creativity and technical advancement in projects throughout the world.

In an engineering first, the bridge's architects designed the slats of the fabricated steel span into a cascade of cantilevers. Each of the five beams has a dedicated concrete counterweight and pivot mechanism; hydraulic cylinders below the pivots, combined with the counterweights, enable them to lift in sequence with minimal effort. When opened, the tallest beam extends like the top rib of a hand fan to nearly vertical, and the lowest rises 2.5 meters above the canal—high enough for small craft to pass underneath. “The fingers can rise and fall at different speeds and to different inclinations—all very innovative,” says Ian Firth, one of the judges of the awards, which will be announced this month.

A simpler structure could have sufficed to provide pedestrian passage across the water. This bridge, however, stands as a work of art, Firth adds, combining form and function in one dazzling display.


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Structural Designers

Knight Architects and AKT II

Length

20 meters

Width

3 meters

Raise/Lower Duration

3 minutes

Steepest Angle When Open

80 degrees

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe