RMIT engineers have once again demonstrated ingenuity in the sustainability innovation sector by devising a way to make stronger and crack-resistant concrete from scrap carpet fibres.
The research team – led by Dr Chamila Gunasekara from RMIT University – is in discussion with Textile Recyclers Australia, Godfrey Hirst Australia and numerous councils in Victoria to facilitate field studies of on-ground slabs made of reclaimed textiles.
RMIT Professor Sujeeva Setunge will oversee the field trials, funded by the TREMS research hub and an early-career research grant.
Strengthening concrete and halting the shrinkage process
Dr Gunasekara – who led an RMIT project earlier this year that discovered the powers of nano-additives in low-carbon concrete – says his team developed a technique that sees waste carpet fibres slash the chance of early-age cracking in concrete by up to 30 percent. This technique also saw an increase in the strength and durability of concrete.
RMIT was primed to take on the task, with the university’s state-of-the-art textile research facilities helping the team of civil engineers and textile researchers uncover the power of carpet to make concrete stronger. Laboratory concrete samples were created from various textile materials and satisfied Australian Standards for engineering performance and environmental requirements.
Responding to a major challenge in construction
This discovery will be hailed as a saving grace in the construction sector, as the annual cost of repairing cracks in reinforced concrete structures in Australia is approximately eight billion dollars.
Gunasekara says cracking in early-age concrete slabs can lead to premature corrosion, alongside lowering the aesthetic value of a building and hindering structural integrity. However, repurposing waste material offers hope, confirms Gunasekara.
“Scrap carpet fibres can be used to increase concrete’s strength by 40 percent in tension and prevent early cracking by reducing shrinkage substantially,” he says.
Capitalising on an opportunity in the materials supply chain
Careless textile and carpet disposal is a worrying environmental problem, particularly in Australia where the average person purchases 27 kilograms of new clothing and textiles every year and tosses 23 kilograms into landfill.
“Australia is the second largest consumer of textiles per person in the world, after the US,” says Gunasekara. “Burning carpet waste releases various toxic gases, creating environmental concerns.”
The results of the RMIT study can be found here.
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