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Commercial “This was an engineering feat in itself, just Steel erection has progressed smoothly since building up to the fifth floor. The new Broadgate May last year, Mr Day says, helped by planning Tower footprint required careful load transfer into that “modularised” the steel pieces where possible the existing raft and this has been achieved by the to reduce pressure on the cranes. Also, secondary design of the A-frames, each consisting of two 20t steel was engineered in the early days of the project box girders of 40mm plate steel. Before these were with service holes and lift shaft and, where possible, fully erected, most of what could be seen on site cladding brackets pre fixed to the steel when it Each A-frame for supporting the A-frames main nodes in the external frame has helped witharrived on site. “Plus, the decision to site-weld thewas temporary steelwork consists of two and floors up to level five,” the required building tolerances,” Mr Day adds. 20t box girders of Mr Day says. deck fixers and welders (it also has a managementHare’s 160 strong workforce of steel erectors,Hare was awarded the 40mm plate steel steelwork contract for both team of 20 on site) is due to finish steel erection and buildings – around 8,000t in floor decking by Spring this year – all decking has the Broadgate Tower and 5,000t in 201 Bishopsgate been cut off site to minimise noise in the vicinity and – in December 2005, two months after starting work Hare’s own proprietary edge protection system has on the 600t of extra raft steel. Erection of the main been used. Concreting of the composite floors, fire steelwork got under way in May last year, with three protection, dry wall partitions and cladding, services tower cranes per building including two jump cranes and just about all of the project’s other trades are inside the tower. now following up behind erection of the two steel “It was quite challenging, coordinating the frames. crane jumps,” Mr Day says. “The cranes were free Column heights have been fabricated at three standing up to floor 11 and then were jumped every storeys to further reduce pressure on the cranes Both buildings are sixth floor, but only after all of the frame erected at and each of the main signature diagonal bracing being constructed with use of Hare’s that point was fully bolted and welded. The majority members in the Broadgate Tower consists of two proprietory edge of the steel fixing has been carried out from three 13.5m welded sections. Clear floor spaces in both protection systems MEWPs (mobile elevated work platform) on each the tower and 201 building have been achieved for safety. building, lifted up every three floors.” with 20m spans and 12m bays, and beam depthsJ0215 kalt_struct_ad.qxd 1/21/05 3:13 PM Page 1 Saw/Drill - close coupled Punch & Shear Coping Kaltenbach Ltd, 6-8 Brunel Road, Bedford, MK41 9TG England tel: +44 (0)1234 213201 fax: +44 (0)1234 351226 email: sales@kaltenbach.co.uk 22 NSC February 2007


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