Works begin on BORR’s Fauna Land Bridge
One of the most unique bridges on the Bunbury Outer Ring Road (BORR) alignment, the Gelorup Fauna Land Bridge, is beginning to take form with the installation of the segmental Mechanically Stabilised Earth walls.
Published: 20 March 2024, Updated: 20 March 2024
The Fauna Land Bridge is unique for a few reasons.
1. Fauna-only bridge
As part of the environmental considerations on the project, several structures have been included into the design of BORR to ensure safe passage of animals from one side of the road to the other. This includes underpasses, rope bridges and an innovative fauna land bridge.
The fauna land bridge will be built over the highway and allow animals to move freely from one side of BORR to the other. The bridge will be important in preserving the local biodiversity and minimising disruption to natural migration routes and species’ movements. To encourage passage, the bridge will include native vegetation and flora, and a design that mimics the surrounding natural environment.
2. MSE walls are ‘segmental’
What do we mean by segmental Mechanically Stabilised Earth (MSE) walls?
‘MSE walls’ is a technical term that refers to the use of mechanically provided stabilisation (i.e., ground based reinforcements) in the earth to ensure the walls are strong enough to support and distribute the load from the bridge abutments effectively.
Being segmental means that the walls are stacked and connected to form the retaining wall to support the abutment structure of the bridge. In other words, on this bridge, the walls are all manufactured and installed in segments that interlock securely with one another. Using segments of walls assembled onsite allows for flexibility in design and efficient construction.
3. Beams cast onsite
The Fauna Land Bridge is the only bridge on the BORR project where the beams will be cast on site.
All of the other bridge beams on BORR have been pre-cast off site and transported onto site for installation. In-situ beams are cast in place allowing for greater flexibility in terms of design and installation, as well as any necessary adjustments that need to be made based on site-specific conditions. Moulds and forms are used to pour concrete onsite to create the various structural elements.
Commencement of work on this bridge is another exciting milestone for the project.
Construction on the MSE walls is underway on site
