Construction feat: The Westmead Metro Station stands as a testament to the technical capability spirit of this ambitious infrastructure project. The installation of the formwork was carried out during a tightly coordinated 82-hour operation. — Sydney Metro
THE Gamuda Australia and Laing O’Rourke consortium has achieved an engineering milestone on the Sydney Metro West – Western Tunnelling Package, with crews at the future Westmead metro station successfully building and installing the largest temporary formwork system of its kind in the southern hemisphere.
According to the Sydney Metro, operation has enabled the lining of the tallest station cavern across its entire network, marking a major step forward for the project.
To line the cavern walls, the delivery team first constructed a colossal, bespoke temporary formwork structure standing seven storeys high and weighing 315 tonnes.
Measuring 21 metres tall, the structure was designed to fit precisely within the tight confines of the underground station cavern, with minimal clearance on either side.
The installation of the formwork was carried out during a tightly coordinated 82-hour operation, requiring careful planning and precise execution.
Using a synchronised jacking and winching system, crew guided the massive temporary arch from the station box into the cavern with just millimetres to spare, before lifting and securing it into place.
Once installed, the formwork acted as a temporary mould, enabling a 1,941-tonne concrete pour to form the cavern’s 2.5-metre-thick walls.
With this stage complete, the Westmead station cavern is now fully lined and stands approximately 26 metres high.
Sydney Metro mentioned that the achievement was the result of nearly 12 months of detailed planning, design coordination and collaboration across multiple teams.
Several crawler cranes were deployed during formwork construction, while extensive underground works were undertaken to ensure the structure could be safely assembled and installed.
The operation was delivered in partnership with Altrad RMD Australia, which designed and supplied the bespoke formwork system, and Kenny Constructions, which invested more than 8,000 hours into the task.
This included pre-assembly works at Eastern Creek, a series of complex crane lifts and the final underground installation at Westmead.
Digital innovation also played a key role in the success of the operation.
Gamuda Malaysia’s Digital Engineering team developed a detailed 3D animation of the assembly and installation sequence.
This allowed the broader project team to visualise each stage of the build, identify potential risks and refine the construction methodology before work commenced on site.
With the formwork operation now complete, works at Westmead are progressing to the next phase.
Crews are currently retrieving the 1,200-tonne tunnel boring machines that arrived beneath the station in September and October, lifting each machine out in sections through an opening in the roof of the acoustic shed above the cavern.
Furthermore, this milestone at Westmead stands as a testament to the technical capability, innovation and collaborative spirit driving the delivery of Australia’s largest infrastructure project, said the Sydney Metro.
