More than a thousand concrete segments for an elevated viaduct have been precast for the Sydney Metro – Western Sydney Airport project.
A facility just outside Newcastle produced all 1101 segments, casting 52,000 tonnes of concrete for an elevated viaduct being constructed for the project. Each segment along the viaduct is 10.85 metres wide, up to 3.2 metres long, and 2.4 metres high.
A two-span section of viaduct has recently been constructed over two pipelines for Sydney Metro – Western Sydney Airport and all but 208 precast concrete segments have been installed. The pipes feed 80% of Sydney’s water from Warragamba dam to filtration plants for treatment.
The team of 30 workers constructed the elevated viaduct with its 26 concrete segments, each weighing up to 65 tonnes and up to 15.3 metres above the pipelines, which were depressurised one at a time for safety and required a significant amount of preparation.
“[It] … was required to strengthen the ground around the pipelines, while rigorous vibration and settlement monitoring was implemented throughout construction activities to ensure the pipelines remained unaffected,” Sydney Metro stated.
“Central to the strategy for protecting the integrity of the pipelines was the use of the Underslung Temporary Beam, a purpose-built crane used to snugly support the [concrete] segments while they were lifted and positioned, eliminating any risk to the pipelines below.”
Reaching this stage in construction, the team can now turn to completing the 3.5 kilometres of elevated viaduct between Orchard Hills and Luddenham. More than 18% remains to be built.
By the end of 2024, the majority of the viaduct and sections of the alignment at ground level will be finished, making way for the commencement of tracklaying.
About the author
Desi Corbett
Desi is the Editor of Concrete in Australia and at the helm of our magazine for 8 years. She was behind the Institute's weekly news bulletins from 2016-2021 and is now writing our focused news items. Desi has been an engineering news and features journalist/editor across all disciplines since 2013 - part of a 30-year career writing for a wide range of industries.