Design and Construction Planning of the Macleay River and Floodplain Bridge

The Macleay River and Floodplain Bridge forms part of the overall Kempsey to Eungai Pacific Highway Upgrade Project and when completed will be the longest bridge in Australia, with an overall length of 3.2km, extending over the Frogmore Floodplain and the Macleay River. The bridge consists of a single structure, 21.6m wide, providing two carriageways separated by a median barrier with two 3.5m wide traffic lanes in each direction, plus an outer shoulder width of 2.5m and inner shoulder width of 1.0m. This paper will cover the following aspects of the project: (a) Description of the site and the final structural and geotechnical design; (b) The development by Abigroup and its designers (Arup and Benaim) of the design of the bridge, from the tendered design through to the detailed design; (c) Key aspects of the design including geotechnical, flood modelling, scour and drainage design; and (d) The challenges for the construction including the installation of 328 steel driven piles and 64 bored piles and the logistics involved in the manufacture, delivery and installation of 941 Super-T girders. The project is currently in the detailed design phase, with construction having commenced in July 2011, with a completion target of December 2012.