Full project details
Laing O’Rourke electrified the 110km railway linking Glencore’s Rolleston Mine to Kinrola Junction at Blackwater in Queensland, using several innovations to bring power to a heavy-haul line that was never built to be electrified.
Smart and innovative solutions overcame the project challenges associated with complex power supply requirements, remote location, very constrained access, significant flood risks and geotechnical conditions while maintaining coal train operations throughout construction.
Careful planning and a culture of collaboration and innovation between the Laing O’Rourke and Aurizon teams, and support from our partner AECOM, overcame the project’s challenges, bringing several new technologies and construction methodologies to ensure delivery in an efficient 20 month timeframe.
Feeding reliable power down the line
The project’s power infrastructure was specifically designed to overcome the out of balance electrical load applied by the railway traction system, on the high voltage supply network. The electrification solution included a 132kV switchyard connected to the existing Ergon transmission network via 5km 132kV transmission line, a 50kV feeder station, a track sectioning yard, several trackside auto transformers compounds, 110km of rail overhead wiring, telecommunications infrastructure and more than 2,300 overhead wiring masts and foundations.
The interface between the 50kV rail network power systems and the 132kV distribution network presented a significant ‘Power Quality’ challenge. Static Frequency Converters (SFC) were used for the first time in the Australian rail industry to overcome this challenge and deliver a reliable, balanced, immunised electrical supply to the rail power network from the high-voltage power grid. This is a radical, energy efficient departure from the prevailing technology and has set a new benchmark for Australian rail projects.
Bringing further international smarts, the team used vertical isolators to connect/disconnect the power supply to the rail overhead wiring system. These isolators offer a more reliable, simpler design of switch that has been successfully used throughout Europe for a number of years.
Keeping off the tracks
A 1966 ex-military Bell UH-1H helicopter (the famous Vietnam-era “Huey”) was used to lift, position and install a significant percentage of the project’s overhead wiring masts. A Squirrel helicopter was later used to run out the optical ground and feeder wires instead of engaging conventional wire trucks and long-reach boom techniques that launched from on or beside the tracks.
This innovative use of helicopters overcame the project’s unique access constraints – the rail line’s footprint was designed for diesel powered trains and was not designed to accommodate the kit required to electrify the line. The helicopters allowed the team to achieve the unprecedented production rates necessary to meet the program. It also reduced the need for on-track time minimising disruption, keeping the coal loaded trains running.
The innovative installation methodology adopted by the team saw production rates up to ten times faster than conventional methods, while also removing high risk construction activities such as using cranes and works at height.
Never built for electrification
The Kinrola line’s rail formation was originally built to run diesel trains and was never designed to accommodate electrification infrastructure. It presented significant challenges in terms of topology, geology and site access that meant conventional reinforced concrete mast foundations simply could not be used in many locations.
In another Australian first, and using our market-leading Design for Manufacture and Assembly (DfMA) approach, our team used prefabricated steel driven piles for overhead wire footings in hard to access areas along narrow steep formations. Some formations were over 14m in height.
The steel driven mast piles were fabricated offsite, providing production, logistics and safety benefits. Using prefabricated mast piles resulted in the installation time for each pile being reduced to around 20 minutes – a standard pile typically takes between 90 minutes and two hours to install.
An Engineering-led approach drives rail industry progress
Laing O’Rourke’s engineering led approach on this project is the culmination of an overarching engineering agenda, which is driven by our vision to challenge and change the construction industry worldwide. The technology and methodology innovations introduced on the Bauhinia Electrification Project have redefined design and construction approaches for rail electrification infrastructure Australia wide. To illustrate, SFCs have already been adopted on major rail projects in Queensland.