Paul Weston, Sarens UK sales manager and project manager on this job, told Cranes Today that the 1,200t capacity lattice boom crawler had been fitted with a 71m jib and 450t of superlift ballast. A 500t capacity, 13m wide, spreader was used, with four 34m wire rope slings supporting each corner of the bridge.

The bridge was assembled in a yard adjacent to the site by fabricators Fairfield-Mabey. Fairfield-Mabey site manager explained that it took around two months to assemble the bridge, starting in mid-January. Two 36m long girders were brought to the site fully welded together; this was a challenge in itself, with London’s medieval road layout making transporting such a long load difficult. Once at the site, thirty 13m cross beams were bolted to the two long girders, like the rungs on a ladder. Once the bridge had been bolted together fully, a further two weeks were needed to paint and waterproof the bridge..

The complete bridge was picked up by the Gottwald, lifted 10m, and then slewed round to cross over a busy road into the City, at a radius of 34m. Particular care needed to be taken to avoid historically important buildings close to the bridge.

Weston said around forty 25t trailer-loads of ballast and lattice work sections were needed to assemble the Gottwald. Rigging and derigging the crane each took three days, and used a 100t mobile telescopic boom crane. The lattice boom crane was crewed by two drivers and two helpers from Sarens, with a third driver operating the assist crane.

The East London line is part of London’s tube system. It is currently closed, while it is extended to connect popular residential areas on the fringe of central London with the financial district in the City. Until now, poor ground conditions in London’s East End had meant that the area was under-served by rail links.

UK TV channel ITV filmed the lift, and a video news report is available online here.