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Australian Welding: September 2020
Australia’s First Double Helix Bridge Now Open The Lachlan’s Line pedestrian and cycleway bridge opened to the public in June 2020. Believed to be the first of its type in the world, the eye-catching, bright blue double helix bridge twists and turns over one of Sydney’s busiest motorways to connect a new residential and mixed-use development, a major business precinct, and a metro station.
The $40 million Lachlan’s Line pedestrian and cycle bridge is a firstof-its-kind—an organic, double helix bridge. It connects Landcom’s new Lachlan’s Line Residential Precinct on its western extremity, to the North Ryde Commercial Sector and Metro Station on its eastern extremity. Bold and bright blue, the bridge is a striking visual landmark, as well as a busy active transport connection. The bridge has transformed access to the Lachlan’s Line site, which
is bounded by one of Sydney’s busiest intersections, that of the M2 Motorway and Delhi Road. Commissioned by Landcom (the New South Wales Governments’ development agency), the Lachlan’s Line bridge project was delivered by a joint venture between Daracon Group and Arenco, designed and engineered by Arup and KI Studio, and fabricated by Weld Australia member, S&L Steel.
The Design At 178m in overall length, the Lachlan’s Line bridge is a variable diameter helical steel truss bridge, curved in plan. As reported by This is Construction, it is the first double helix bridge in the world to have a variable diameter, which increases in size over the supports (where bending moments are higher) and narrows midspan (where moments are lower). These eye-catching
