An innovative steel canopy used on the construction of a development in Singapore has now been dismantled as the project moves towards completion.
Japanese contractor Shimizu used its mechanised building platform system on the Housing & Development Board’s new headquarters building in Tao Payoh (Japanese canopy covers Singapore site Nov99, p27). The project comprises a 28-storey tower block, a 33-storey tower, and a mix of five-, six- and nine-storey buildings.
The massive platform, measuring 92.7m long by 50.8m wide, sat on seven ‘super beams’ supported by seven masts. The platform allowed work to continue during adverse weather and permitted construction of large column-free areas with six gantry cranes fitted beneath the platform. As work progressed, the platform was jacked three storeys at a time.
The project is not completed until the middle of next year, but the so-called ‘Smart System’ platform is no longer required and was dismantled in February.
The ‘super beams’ each weighed 28t and so were cut into 7t sections for dismantling. They were lifted down by the three Potain MR 150 luffing jib tower cranes that were used on the project, with each section being tandem lifted by two cranes.
The MR 150 has a 40m jib and a maximum lifting capacity of 5.9t at a 30m radius. All three units are fitted with Potain’s 55RCS20 winch system. In two-fall mode, the crane has a maximum speed of 104m/min at 2t and 26m/min at 8t with four-fall operation. The cranes have a drum capacity of 1,000m for lifting to on-site heights of 160m.
Throughout construction, Shimizu has used eight Potain cranes. In addition to the three MR 150s purchased by the contractor from Potain distributor Manta, a fourth was hired from Manta’s rental fleet, together with three MD 345 cranes and an MD 285.
The three MD 345s feature a mix of 40m, 50m and 55m jib lengths with respective hook heights of 51.4m, 31.4m and 39.7m. For the first time in a multi-application in Singapore, the cranes all featured Potain’s Top Tracing anti-collision system.
