Western Australia’s North West Coastal Highway serves as the main link between the regional centres of Geraldton, Carnarvon, Karratha and Port Hedland as well as between the surrounding coastal, mining and farming communities. It also provides access to popular tourist destinations including Exmouth and Onslow.
Traffic on the highway has steadily increased over the past few years following the expansion of the oil and gas industries in the northern Gascoyne and southern Pilbara. According to Western Australia’s Main Roads Department, 37 per cent of all traffic on the highway is heavy vehicles.
In order to improve water crossings and to increase safety and access, the department announced an upgrade of parts of the highway. This included an upgrade of the Goodeman and Cave Creek Bridges, the remote location of which was always going to prove challenging.
Precast concrete bridge beams
Perth-based precast manufacturer and National Precast member Delta Corporation became involved in the project at the early stages. Executive Director Matt Perrella says his company was proactive in finding a precast solution for the bridge components of the upgrade.
“We approached the contractor because we believed we could do the project in a more economical way,” he says. “We asked them to look at a redesign to incorporate precast, rather than steel beams.”
Mr. Perrella says his team was confident of coming up with a better solution for the build. Despite a redesign, Delta was able to meet the contractor’s budget and timeline for the project.
Standard trucks to speed delivery and reduce cost
Delta manufactured 32 custom-made prestressed TeeRoff beams for the two bridges. The largest was 20.75 metres long, 2.75 metres wide, almost one metre deep and weighed 39.5 tonnes. The precaster was mindful of the weight of each beam in regards to transport to such a remote site. The beams had to be taken about 1300 kilometres north to the project site. Keeping the beams within a weight limit ensured standard trucks could be used, which cut down the time required and the delivery cost.
“We’ve produced beams for many bridges, but what made this project different was the location, which was very remote,” says Mr. Perrella. “Quite a few things needed to come together. We had to make sure we worked with the contractor to ensure the design and detailing was correct. If it’s wrong you’ve got a big problem, so we checked and re-checked that production was top quality for accuracy.”
He says the contractor was very happy with the project outcome and the economical precast solution.
Open for business
The new bridges at Cave and Goodeman Creeks have now opened. The Main Roads Department says their construction will reduce the likelihood and length of highway closures and traffic delays caused by flooding. It is good news for the road train traffic using the highway to transport freight, as well as the heavy transport for the oil and gas industries. It also reduces the risk of local communities being cut off during times of heavy rain and flooding.