29 April 2012

London Bridges: 27. Bridge of Aspiration

This post brings to a close my recent series of posts featuring bridges in London. Sadly, unlike the Plashet School Footbridge, I couldn't get permission to visit the interior of this one.

The Bridge of Aspiration links the Royal Ballet School with the Royal Opera House, spanning over Floral Street in Covent Garden in London.

It was designed by Wilkinson Eyre with Flint and Neill, and is admirably simple in its conception. A square cross-section rotates through 90 degrees from one end to the other, creating a fusilli-like twisted form. The two end portals are not directly opposite each other, and as can be seen from below, the bridge's geometry provides a rational way of dealing with the requirements of a skewed crossing.

Structurally, the primary element is an aluminium box girder, which helps reduce the weight and hence the loads on the supporting buildings. The girder twists in such a way that it is shallowest at its ends (rectangular in cross-section), and deepest at midspan (triangular), as befits the bending moment diagram.

The girder supports a series of square frames, with glazing between them, each of which is rotated approximately 4 degrees relative to its neighbour.

It's a very special bridge, both in how it responds to the geometric needs of the site, and in how the structural form combines the rational with the idiosyncratic. I expect that it's essentially unrepeatable, difficult to imagine it being re-created anywhere else. Judging from the various interior photos I've seen, my exterior photos fail to capture most of what makes it so charming, but even from this perspective, it's a very fine bridge.

Further information:


Bridge Ink said...

Can you comment as to why you were not allowed to photograph the interior?

The Happy Pontist said...

It's a private bridge linking two buildings, open only to occupants. I wrote to the Royal Ballet School asking if I could have a look inside, but got no reply.

Bridge Ink said...

Maybe you should get friendly with a ballerina.

Gary Wall said...

For anyone interested, there is a photo of the inside of the bridge and some detailing in the book "Footbridges - Structure Design History" by Ursula Baus and Mike Schlaich. It is great book for anyone with an interest in this subject and features bridges from all over the world. It also has a few of Mike's bridges as well as some of his father Jorg Schlaich.