Olympic Aquatics Centre roof work begins - PHOTO and VIDEO

The first longitudinal roof truss has been lifted into position on the London 2012 Aquatics Centre.

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Main contractor Balfour Beatty is overseeing the work and the steelwork has been fabricated by Rowecord Engineering.

Work on the 2800 tonne wave-shaped roof of the Zaha Hadid designed London 2012 Aquatics Centre is considered one of the most complex engineering and construction challenges of the Olympic Park ‘big build’.

The steel being lifted to form the 160m long, 11,000m² sweeping roof is fabricated in Newport from plate rolled in Gateshead, Motherwell and Scunthorpe.

ODA chief executive David Higgins said: "The Aquatics Centre is on track to be a fantastic gateway to the Games and provide swimming and diving facilities in legacy that London does not currently have.

"The lift of the sweeping wave-shaped roof is one of the toughest construction and engineering challenges on the Olympic Park and will showcase the world class expertise involved in delivering the venues and infrastructure for London 2012.

Architect Zaha Hadid said: "It is very exciting to see such progress on site. This is a key milestone in the construction programme we have been looking forward to since winning the 2004 competition. The roof of the Aquatics Centre reflects the fluidity of water and will provide an inspirational legacy for all Londoners well beyond the 2012 Games."

When complete the 160m long column-free and up to 90m wide roof will rest on two concrete supports at the northern end and a 28m long and 5m wide,  supporting ‘wall’ at its southern end.

A huge 30m steel truss weighing over 70 tonnes has been lifted into place on top of the southern wall. This has already been connected with the first sections of 15 steel trusses which will span up to 120m to the two northern roof supports.

Over the coming months steel trusses fabricated in Newport from plate rolled in Gateshead, Motherwell and Scunthorpe, will be assembled on the Aquatics Centre site and connected together 20m off the ground on three rows of temporary support trestles.

Once the huge steel roof frame is complete it will be lifted up to two metres at its southern end, turning on complex rotating joints in the northern roof supports. The temporary trestles will be removed and the 160m long roof frame lowered on to its three permanent roof supports, which have been built with over 20,000 tonnes of concrete.

As the full weight of the roof rests on its supports it will slide approximately 20cm into its joints at the southern wall. The roof has been designed, through wind tunnel testing and computer modelling, to stretch, twist and contract in response to the effects of snow, wind and changing temperatures.

Once the steel roof is in place this summer work will begin on the aluminium roof covering. Installation will then start next year on the timber cladding of the ceiling which will sweep outside to cover the northern roof supports.

The foundations of the permanent venue are complete and work will begin on the pool structure once the steel roof is complete.