Recycled glass heralded a success in concrete road mix trials
June 14, 2019 – Australia’s largest regional infrastructure project has included tests in which recycled glass has replaced sand in the highway’s concrete mix.
New South Wales (NSW) Roads & Maritime Service acting director northern Vicky Sisson said that the project team for the Woolgoolga to Ballina upgrade recently completed two successful pavement trials using recycled glass in the concrete mix.
She said that a grant for the trials was awarded by the NSW Environment Protection Authority. “Recycled glass has previously been used for ramps and drainage but this is the first time it has been used on the main carriageway on the Pacific Highway,” she said.
The glass was collected locally from Lismore City Council’s waste collection system, which includes household recycling bins and ‘return and earn’ stations. “After being sorted, the glass was crushed into sand at Council’s material recovery facility, delivered to on-site batch plants for cleaning before being mixed with sand, and used in the normal concreting process,” said Sisson.
The recycled glass sand was used in place of sand quarried for the purpose, reducing material consumption and waste at the same time. “The mix meets Roads and Maritime Services’ specifications for concrete pavement and will be tested for quality in the same way as traditional concrete pavement,” she said. “The good news is this mix will not require any additional maintenance. It’s exciting to see this new market grow and it is hoped recycled glass is used on more NSW road projects in the near future.”
NSW Environment Protection Authority’s executive director for waste and resource recovery, Carmen Dwyer, said the AU$107,636 grant was awarded through the ‘Waste Less, Recycle More’ programme, which aims to stimulate new investment and transform waste and recycling across the state. “Working with large organisations in the civil construction industry creates great opportunities to reduce landfill and support new markets and opportunities for recyclable materials, reducing the impact of changes in the global recycling market,” she said. “These grants aim to foster innovative thinking while removing the potential risks associated with implementing new processes.”