London’s Olympic Stadium raises the roof

London’s 2012 Olympic Stadium has reached another construction milestone as the cable net roof is lifted into place, ensuring the Stadium remains on target for completion by mid-2011. The 450 tonne cable net, which took four weeks and 56 hydraulic jacks to lift, is formed between the outer, white steel roof truss and an inner tension ring 30 m above the field of play. According to the Olympic Delivery Authority (ODA), over 900 tonnes of scaffolding and over 1 km of support platforms were used to assemble the 12000 m-plus of cables and walkways. Next year, a 650 tonne crane will be assembled in the middle of the Stadium site to lift the 28 m-high lighting gantries on to inner ring of the cable net roof, taking them 60 m above the field of play.