BRIDGES IN FOCUS
BUILDING BRIDGES IN THE AFTERMATH OF THE BUSHFIRE CRISIS
Between September 2019 to March 2020, bushfires burnt over 18.6 million hectares across Australia. The path of destruction has left towns desperately trying to pick up the pieces of their communities. Homes, buildings and infrastructure are now beginning to be rebuilt after the damage. For many regional towns, bridges are the only ways in or out of their community. When a bridge has been damaged, the impact on the local community can be significant, particularly if the bridge is one of only a handful of access points connecting the region. Bridges form a vital part of Australia’s transport network, with around 30,000 timber road bridges in service throughout the country. However, due to heavier and faster moving vehicles and more recently, damage by bushfires, many of these ageing timber structures have deteriorated or damaged beyond repair and Councils are needing to look at ways to reconstruct the infrastructure with a time and budget effective solution. As a way to extend the life of existing timber bridges or build replacement bridges, Australian timber specialist and plywood manufacturer, Big River Group, has developed an engineered timber system consisting of bridge decking, girders, headstocks and corbels along with many other engineered sections that replace existing timbers size for size, a structural grade Engineered plywood bridge deck system which acts as an alternative to steel and concrete decks being less expensive, faster to install, and a critical measure of success for those locations who are lacking council funding and are needing a quick
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response. The system is an Engineered substitute for traditional hardwood decking and is manufactured to AS/NZS 2269-2008 from sustainable Australian plantation pine. The key feature of the Big River Engineered Bridge Decking is the it is manufactured in continuous lengths to the full width of a bridge hence providing excellent load distribution utilising the full structure and extensively extending the life of existing structures when used as a deck replacement. When the fully Engineered system is used with the combination of Engineered LVL: girders, headstocks and corbels etc this delivers a full Bridge system that complies with loadings and AS:5100 T44 deflection limits as well as M1600. As a retrofit solution that can help extend the life of timber bridges by decades, Bridge ply, offers a low-cost option for rehabilitating existing, older timber structures without needing to replace the entire bridge – meaning only components that are failing need to be replaced, saving time and material costs. Cedar Creek Bridge, in the Hunter region of New South Wales, was restored in three days – four days ahead of deadline, with council contracting two work crews aroundthe-clock to complete the job quickly. The larger size of Bridge ply helps to absorb much of the extra vibration of heavy vehicles while also tying together the other timber components of the bridge better than solid hardwood planks. What’s more, the material holds fire resistant qualities which have the ability to withstand temperatures that reach 1,000°C for up to 50 minutes.
Providing a time efficient solution due to its lightweight feature, Bridge ply can be moved in large sections with the same machinery used for alternative materials, so less trucks are required for delivery and less crane movement is needed in order to connect the components. Additionally, as a timber-based product, most of the machinery alterations, can be done on site with hand tools, such as drilling. All of these benefits, together with its lightweight material, means installation can occur in a timely manner with minimal disruption to the local community. Big River Group are offering drop-in services and temporary bridges for immediate solutions to reconnect communities, whilst strengthening and recovering existing timber bridge assets quickly and within council budget. For more information visit: www.bigrivergroup.com.au/product/ structural-plywood-bridge-decking
ABOUT BIG RIVER GROUP Big River Group manufactures and distributes timber and steel formwork products, timber flooring, structural plywood and related timber products, and distributes a broad range of other building products, including MaxiWall and MaxiFloor, primarily to the commercial and residential, non-residential and infrastructure construction market segments. Big River owns and manages 17 sales and distribution outlets including Sydney, Gold Coast, Brisbane (2), Sunshine Coast, Townsville, Illawarra, Melbourne, Canberra, Geelong, Adelaide, Perth and New Zealand. The Company also owns and operates manufacturing facilities at Grafton and Wagga Wagga in NSW, Geelong, Perth and Auckland NZ. Big River provides customers with the security of a full support network, and technical expertise at every stage of the product lifecycle. This is the guarantee of quality and service that Big River has based its 110 years of success on.
