INDUSTRIAL WASTE
CONCRETE TRIAL THE CITY OF SYDNEY AND THE UNIVERSITY OF NEW SOUTH WALES ARE TESTING CONCRETE MADE USING INDUSTRIAL WASTE FROM COAL-FIRED POWER STATIONS AND STEEL MANUFACTURING.
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ccording to UK non-governmental organisation Royal Institute of International Affairs, cement is the source of around eight per cent of the world’s carbon dioxide emissions every year. The extensive carbon footprint has for decades prompted researchers to look for new and greener solutions to construction. One alternative that has been looked at is geopolymer concrete. The material aims to significantly reduce CO2 emissions and is made using recycled industrial materials. Geopolymer concrete has been researched since the 1990s, including in the research
paper Geopolymeric concretes For Environmental Protection, published in Concrete International in 1990. However, despite ongoing research efforts, practical results showing its durability and performance have only come into the spotlight during the last five years. For the first time, the City of Sydney is trialling geopolymer concrete on a busy city road. It estimates the alternative only produces 300 kilograms of CO2 per tonne compared to 900 kilograms per tonne with traditional concrete. The City of Sydney is trialling the
geopolymer concrete on Wyndham Street in Alexandria, a road leading to the airport. The concrete is made using fly ash from coal-fired power plants and blast furnace slag, a bi-product of the steel manufacturing industry. The road has been constructed with 15 metres of traditional concrete and 15 metres of the ‘green’ geopolymer concrete. The even spread ensures each section receives the exact same amount of traffic. Lord Mayor of the City of Sydney Clover Moore says projects like this can result in new products that can make a real difference
The City of Sydney is trialling the geopolymer concrete on Wyndham Street in Alexandria.
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ROADS SEPTEMBER 2019
