Toowoomba Second Range Crossing project delivers engineering milestone for key viaduct

The Ferrovial Agroman Acciona Joint Venture has installed the first girder in one of the most challenging engineering elements of the 41km Toowoomba Second Range Crossing The 800m long viaduct is one of the main engineering features of the Toowoomba Second Range Crossing project and will negotiate the steep terrain of the Toowoomba Range. The viaduct is being built using construction technologies that consist of a jump form system for the individual bridge piers and a launching truss gantry for the installation of the Super T girder beams that will form part of the bridge deck. This is the latest in a long line of milestones and project achievements. From May 2016, early works cleared the viaduct area by removing thick vegetation, establishing access tracks and preparing platforms for the piling works. A mobile concrete batching plant was also set up in the area to make concrete for the viaduct. Piling for the foundations of the piers of the viaduct was completed in January 2017. The piles are between 6 and 20m deep, depending on the section of the viaduct they are supporting. In October 2016, pier construction commenced. Piers are constructed in 4.5m lifts with a jump form technique that climbs up as each section is poured to a maximum height of 51m. Headstock construction commenced in December 2016. Headstocks are built on top of the piers to carry and support the bridge deck. To complete the viaduct, the final stage is to construct the bridge deck. Constructing the bridge deck includes the installation of large precast concrete beams (Super T girders) precast formwork, steel reinforcement and a number of large concrete pours. The Super T girders will be installed using a launching truss gantry, which picks up the girders and positions them to be fed through to the back of the gantry, and over the previously finalized section. The gantry then 'launches' into its next position. From May 2017, girder spans will be installed over a three week period, followed by four weeks of pouring four concrete decks to form the bridge deck. Installation will continue in this fashion until complete.

About the Toowoomba Second Range Crossing

The Toowoomba Second Range Crossing is the largest Commonwealth government commitment to a single road project in Queensland's history. Nexus Infrastructure, a consortium formed by Ferrovial through its subsidiary, Cintra, Plenary Group and Acciona was awarded the project in August 2015, with Ferrovial Agroman and Acciona delivering the design and construction. The image shows the first girder is launched into position on the viaduct.