ACCIONA, as part of the Nexus consortium, is progressing with construction of the 817-metre longviaduct that will form part of the Toowoomba Second Range Crossing Project (TSRC), a bypass that will take heavy vehicle traffic around Toowoomba’s CBD rather than through it.

Installation of the viaduct’s girders is a critical activity in the project, due to its technical and logistical complexity.

The girders are manufactured by two factories in Brisbane using traditional pre-stressed production methods with quality control performed by the manufacturers and the project team. The girders are then transported on wide-load transporters to the bottom of the Toowoomba Range where police escort them through Toowoomba’s CBD. The girders are transported at night (four at a time) as temporary road closures are required and also to minimise disruptions to commuting traffic.

A launching gantry is then used to hoist and install each of the 242 girders into their final position.

A team of 13 people is involved in launching and positioning each girder to ensure the accuracy and safety of the works, one of ACCIONA’s priorities in every project it undertakes. In order to construct the viaduct, the Nexus consortium need to navigate steep terrain and minimise disruptions to rail line operations.

The project is approximately 50% complete, with the earthworks moving around one million cubic metres every month.

Once completed, the highway will improve traffic conditions in the region, reducing the volume of heavy goods vehicles and hazardous goods that currently pass through the city centre.

The 41 kilometre bypass will link the Warrego Highway at Helidon Spa in the east to the Gore Highway at Athol in the West, via Charlton. The project’s key features, in addition to the viaduct over the railway line, include a 30-metre deep cutting through the Range as an alternative to a tunnel solution, to allow heavy vehicles, including hazardous good carriers, to use the new tollroad.

ACCIONA Concessions is part of the Nexus consortium, which also includes Cintra, Ferrovial, Plenary Group and Broadspectrum. The consortium was awarded the AU$1.6 billion PPP contract in August 2015 to design, construct, operate and maintain the TSRC.

The works, which will be partly carried out by ACCIONA Construction, are scheduled for completion in 2018 and are expected to support up to 1800 direct and indirect jobs during the life of the project, including up to 700 direct jobs on site with the remainder created by the significant flow-on effects on the wider regional economy. Once the highway comes into service, it will be operated and maintained for a period of 25 years.