|
View previous topic :: View next topic |
Author |
Message |
Dr. N. Subramanian General Sponsor
Joined: 21 Feb 2008 Posts: 5538 Location: Gaithersburg, MD, U.S.A.
|
Posted: Wed Oct 07, 2020 3:27 am Post subject: The Lachlan’s Line pedestrian and cycle bridge, Sydney |
|
|
The Lachlan’s Line pedestrian and cycle bridge, Sydney
The Lachlan’s Line pedestrian and cycle bridge is a first-of-its-kind - an organic, double helix bridge that will connect both Landcom’s new residential development and the Macquarie Park precinct to the North Ryde metro station in Sydney.
Bold and bright blue, the bridge is a striking visual landmark as well as a busy active transport connection.
Arup’s design with KI Studio architects has transformed access to the Lachlan’s Line site, currently bounded by one of Sydney’s busiest intersections – the M2 Motorway and Delhi Road.
Irregular geometry and a more fluid shape
The curved, fabricated box section construction takes helix design and fabrication to a new level with its irregular geometry and a more fluid shape – all enabled by Arup’s digital approach to structural geometry, engineering and design for the permanent design, temporary works and construction sequencing.
The bridge alignment – defined by the minimum feasible length and pier locations - has driven a sinuous structural form.
the use of curved plate fabricated box sections was more than an aesthetic choice: it enabled each side of the section to be optimised with different plate thickness responding to section demand, ensuring the absolute minimum quantity of steel was used. Where design innovation pushed boundaries, the team applied stringent modelling, verification and prototyping to ensure the bridge would meet the highest standards of engineering.
The digital design also enabled more interactive engagement with client and community stakeholders, positive and timely outcomes around updates for the widening of Delhi Road and less impact on nearby vegetation.
Fabricating and erecting the structure
No two pieces are alike in this structure, with the steel varying in curvature, while maintaining uniform element sections. The length and geometry of the bridge were optimised as the shortest length between the two landing points, while achieving the necessary vertical clearances – the outcome being a sinuous form completely dictated by function. The helix varies 2.3m in diameter in relation to varying structural demand: it is 7.8m in diameter at its widest and 5.5m at its slimmest.
Arup worked with S&L, the project steel fabricators, to understand their requirements and to produce a 3D model of each piece of steel.
The software developed by Arup analysed 164 unique doubly-curved node surfaces. To simplify fabrication, the software found their individual best fit equivalent cylinder, allowing us to provide simple roll radiuses and roll directions. This allowed the steel fabricator to unroll the geometry – imagine creating a flattened version of the 3D shape – and laser cut these shapes from a steel sheet.
The 170m steel structure has been built by the fabricator in four separate spans on a nearby site.
Arup developed and designed transportation and lifting assemblies for each segment and part segment that enabled handling and transportation without overstressing the permanent elements.
Lachlan’s Line represents the meeting of engineering skill with digital knowledge, showcasing the possibilities for digital designs of the future.
Source: https://www.arup.com/projects/lachlans-line-bridge-sydney |
|
Back to top |
|
|
|
|
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum You cannot attach files in this forum You can download files in this forum
|
|
|
|