Magnetic Island’s tourism industry has been enhanced with a new floating walkway linking Nelly Bay and Arcadia Bay. A bold and clever design provides a safe access route for pedestrians and cyclists while offering sweeping views of the beaches and terrain. The walkway was designed and built in careful consideration of the natural surroundings on one of Australia’s most unique tropical islands.
Running adjacent to Arcadia Road, the walkway is made up of a 300m long by 2.5m wide on-grade footpath and a 410m long by 2m wide elevated walkway.
The elevated walkway component of the project was both technically and logistically challenging due to its location and the difficult site terrain. Working with Townsville City Council, Tippett Schrock Architects and Thinc Projects, Arup developed a unique solution to which cantilevers prefabricated walkway decks from micropiled foundations to float out above the adjacent cliffs and ocean.
Off-site pre fabrication of complete deck segments allowed the walkway panels to be quickly and efficiently lifted into place, minimising dangerous on site activities along the cliff edge.
Designed for durability
A key requirement for the project was to design the walking using materials which require minimal maintenance and are durable for a 30 year lifespan in tough climatic conditions including extreme weather conditions and tropical cyclones. Through a process of research, design and whole of life cost analysis, precast concrete was chosen for the primary spanning structural element, composite fibre for the secondary beams and galvanised and stainless steel for the balustrades.
Due to the rocky nature of the elevated walkway, a series of steel micropiled foundations connected by cast in-situ reinforced concrete pilecaps were chosen to support the precast decks and resist the design loads.
Council praised Arup’s innovative solution while meeting their brief for durability, safety and budget on this high profile project. The $4.7m walkway was publically opened in March 2013.