Bunbury Outer Ring Road

Targeted embankment monitoring providing real-time and manual insights to optimise preload design and safety for WA’s 27km freight bypass

The Bunbury Outer Ring Road Project

Bunbury Outer Ring Road (BORR) is a 27-kilometre section of highway connecting Forrest Highway to Bussell Highway consisting of three sections – northern, central, and southern. The primary goal of this project is to enhance the region’s freight capacity, efficiency, and productivity. The construction of BORR is carried out by the South West Gateway Alliance (SWGA), providing an alternative route around Bunbury and effectively separating local and regional traffic.

The Challenges

To ensure the success of the project, regular monitoring of bridges, embankments, and abutments was essential. The project includes several bridge abutments that required instrumentation to monitor the imposed loading on the embankment. The imposed loading of the proposed bridge abutment embankments would result in ground settlements that exceed the maximum allowable settlement criteria. As a result, ground improvement and preloading were required at the embankment sites. However, there were significant uncertainties about the duration of preloading required to achieve minimal future settlements and the magnitude of final settlements over the life of the embankments.

What we Delivered

To address the uncertainties of the ground response, the embankments have been instrumented in order to calibrate the design model and parameters. Sixense has provided and  installed a range of instrumentation at the embankment sites. Some sensors were equipped with dataloggers for real-time data transfer, while others required manual reading. Sixense also provided training to SWGA, enabling their technicians to perform ongoing manual monitoring. The collected monitoring data from all instruments was consolidated within Geoscope, allowing for interactive views and graphs of the data. Geoscope also handled automated alarms and facilitated automatic report generation and distribution to the project team.