Central Station Raises the Roof: Northern Concourse Canopy Taking Shape
The roof canopy over Sydney Central Station’s northern concourse is taking shape. Over two thirds of the sweeping prefabricated steel-framed roof has now been erected by head contractor, Laing O’Rourke, and their subbies.
The 2,240 sqm roof designed by Woods Bagot and John McAslan + Partners comprises eight hockey stick-shaped girders, up to 30-tonnes and 21 m long, which support prefabricated steel assemblies that make up the roof structure.
“The 80-metre-long and 40-metre-wide roof extends from the northern end of Platform 8 to Platform 16, and will sit more than 16 metres above ground to enable natural light to filter into the station,” Transport Minister, Andrew Constance, said.
Laing O’Rourke and structural engineers, Aurecon, designed the steel components to allow rapid erection during short nightshift windows, so the station can remain fully operational as work progresses.
“Using Laing O'Rourke's Design for Manufacturing & Assembly (DfMA) approach, key components were produced off-site at Kurri Kurri and trucked in for installation just prior to a 48-hour possession window – ensuring minimum disruption to station operations,” says Laing O’Rourke’s LinkedIn post.
The steel components were manufactured by mining and civil engineering specialist, Alfabs Engineering Group, in the Hunter Valley town of Kurri Kurri, and underwent a trial assembly in the yard before being dismantled and taken to Sydney in the middle of the night.
Alfabs also worked on the construction of Central’s Sydney Yard access bridge, which is being used to truck construction materials for the new metro over the railway lines.
The canopy roof is clad with perforated aluminium cladding panels including 21 distinctive diamond shape skylights, designed and supplied by JML Craft, to allow natural lighting.
“The lightweight canopy will dramatically over-sail the heart of the station as part of Sydney Metro, joining new and old to create a recognisable place and represent the heritage of Central Station to the people of Sydney,” says Woods Bagot’s website.
The 330 tonne roof is expected to be completed at the end of the year whilst Central Walk, a new 19-metre-wide underground pedestrian concourse also being delivered by Laing O’Rourke, will be opened to customers in 2022.
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