Concrete success set to beam ‘em up
A NEW form of super-strong reinforced concrete that will not fall victim to concrete cancer has passed a crucial performance test, clearing the way for it be used to build two pedestrian bridges in Geelong.
Designed to go 100 years without maintenance, it’s anticipated construction of the two 10m bridges will attract wide interest due to the financial and environmental advantages they promise.
The bridges, set for construction in October, are being built by a consortium led by Geelong engineering firm Austeng, which won a pioneering procurement for innovation project put out to tender by the city council.
Deakin University civil engineering experts Kazem Ghabraie and Mahbube Subhani completed the design of the bridges using more durable carbon and glass fibre reinforced polymer as an alternative to steel-reinforced concrete that cracks once the steel starts to corrode.
Representatives from Deakin, Austeng, the council and Geelong Manufacturing Council, which helped enable the procurement for innovation tender, were on hand on Thursday to see a 3m beam made from the new material tested to failure at Deakin University.
Importantly, the beam not only proved many times stronger than steel but also showed visual signs of distress, such as bending and cracking, before it failed completely.
Dr Subhani said the test showed the product “ticked all the boxes” for civil construction and had applications beyond bridges.
“This can definitely be used for building,” Dr Subhani said.
“The interesting part for the construction industry to adopt this technology, is that it has almost zero maintenance costs that we know.”
He said the concrete had been made using a by-product of coal combustion, making it more eco-friendly option than cement, which was responsible for 7 per cent of the world’s carbon dioxide emissions.
Austeng director Ross Geoerge said the test validated the researchers’ calculations and work would now proceed on developing 10m beams to install in North Geelong.
“We have the confidence that we can make full-length beams and put them in place at Cowies Creek and the City of Greater Geelong will have the world’s first carbon fibre reinforced geopolymer beams with 100 years maintenance free,” Mr George said.
The Geelong council’s senior business and industry engagement officer, Tina Perfrement, said the cost of the bridges, at a little more than $200,000 each, was comparative to other methods.
“This is a product that won’t just be for City of Greater Geelong purchases, it is likely to be of interest to plenty of other councils and developers throughout Australian and globally,” she said.
The project is being undertaken by Austeng, carbon fibre research facility Carbon Nexus and geopolymer concrete manufacturer Rocla.