The helix consists of 320 unique members each fabricated from mild steel plate of varying thickness, depending on structural demand. The deck is fabricated from Duplex stainless steel and does not contribute to the structural performance of the bridge. The substructure is also fabricated from Duplex stainless steel, with the exception of Pier 2, which is post-tensioned concrete.
The helix was constructed in four segments which were each assembled in a temporary shed on-site. The largest and most complicated lift was Segment 2 over the M2 which weighed 110 tonnes and required a 600-tonne crawler crane with load cells to manoeuvre the segment into position. The longest, 70 metre bridge spans over Delhi Road was constructed in two segments, with a temporary pier required until welding between the segments was completed.
Cardno were engaged by Landcom to perform Project Verification services for both the design and construction phases. Cardno conducted design verification reviews for the 15%, 50%, 85%, 100%, and IFC stages. Their construction phase services consisted of site surveillance and reviews of quality documentation.
Landcom also engaged KI Studio as Architect, Arup as designer, and Arenco-Daracon Joint Venture to construct the bridge. S&L Steel were the steel fabricators and TfNSW have become the asset owner.
The Lachlan's Line Bridge project is an award winning project:
- The Architecture Community 2021 World Design Award (Landscape Design Built)
- Master Builders Australia Excellence Award - National Civil Infrastructure Award (over $25 million)
- Master Builders Association of NSW Award for Best Civil Engineering Project
- Master Builders Association of NSW Award for Best Use of Steel.
The bridge was opened to the public in May 2020 and safely connects Macquarie Park and the North Ride station for pedestrians and cyclists. The addition of the bridge makes it easier for people in the community to access public transport.
The bridge also adds a striking aesthetic the community can be proud of.