Marching test for wobbly bridge

Engineers hope to reopen the bridge in summer 2001

Nearly 300 engineers and their colleagues marched up and down London's Millennium Bridge on Tuesday to test its new anti-wobble equipment.

The pedestrian bridge which spans the Thames between St Paul's Cathedral and the Tate Modern was closed to the public within days of its June opening because of an extreme wobble.

But Arup - the engineering firm behind the bridge - believes it has come up with a way to stop the sway, without damaging the striking design of the bridge.

The walk on experiment followed a successful test by a "mechanical shaker" and its results raised hopes that the structure could be reopened by summer 2001.

A marching test earlier this year

Arup chairman Bob Emmerson said the mechanical test had produced "exactly the quantity of damping that we predicted".

As a result he is confident the new dampers, due to be installed in the new year at a cost of £5m, will stop the excessive sway.

The 320m footbridge was dubbed the "blade of light" by its makers who included sculptor Sir Anthony Caro and architect Lord Foster.

It was inaugurated by the Queen in May and used by about 150,000 visitors in the first three days of opening on 10 June.

But the "synchronised footfall" effect of hundreds of people stepping in unison triggered such an alarming swaying motion the engineers decided to close the bridge.

Arup hopes it will be reopened by the end of the summer.