• Sectors: Transportation, Public Sector, Highways and Intelligent Transport Systems, Contractors

New England Highway Upgrade at Bolivia Hill

Bolivia Hill, NSW - The NSW and Federal governments are funding the $80 million upgrade to the New England Highway at Bolivia Hill to improve road safety and traffic efficiency. The existing highway has a poor crash history due to narrow lanes and road shoulders, a rock face on one side and a steep rock valley on the other.

2km

upgraded highway

320m

long balanced cantilever bridge

The project is about two kilometres long on the New England Highway at Bolivia Hill, 35km south of Tenterfield, NSW. The upgrade involves realigning the highway to remove dangerous curves, the construction of a 320m long cantilever bridge and high retaining walls in order to straighten the alignment, as well as various ancillary works.

Arcadis was engaged by Roads and Maritime Services to undertake the concept design, detailed design, investigation and construction documentation, along with a review of environmental factors (REF) for the project. A major part of the upgrade involves a cast in-situ concrete box girder bridge constructed by balanced cantilever methods. The three- span structure has a span configuration of 86m, 150m, 80m with the lack of symmetry due to the local site constraints, namely the Bolivia Hill Wattle and the steep terrain on the site. Arcadis worked closely with Roads and Maritime to develop a number of alternative bridge options, including construction access and temporary works requirements, and selected the three-span configuration after it was found to be the best solution which met all project objectives.

The bridge is founded with pad footings on the granite rock with the two piers consisting of twin blade cast integrally into the superstructure. The superstructure varies between 8m deep at the piers to 3.5m deep at mid-span, with 40m long haunches. An asymmetric cantilever tendon stressing sequence was adopted to account for the varied span arrangement with external post tensioning also adopted within the design.

Safety during construction and maintenance was a key consideration, with a number of features incorporated in the design, such as provisions for bearing replacement, a maintenance walkway inside the box girder, and no longitudinal drainage pipes on the superstructure.

Video courtesy of Roads and Maritime Services.

Outcomes

2km

upgraded highway

320m

long balanced cantilever bridge

Improved

road safety and traffic efficiency

Questions about this project

Jarrod Hitchcox

Business Leader - Civil Structures NSW +61 (0) 2 8907 3967 Ask me a question