A research team in Australia has found that waste carpet material can be used to improve concrete used by construction industry. They have developed a technique using waste carpet fibres to reduce early-age shrinkage cracking in concrete by up to 30%, while also improving the concrete’s durability.
- Laboratory concrete samples have been created using the various textile materials and shown to meet Australian Standards for engineering performance and environmental requirements.
- The team of civil engineers and textile researchers led by lead researcher Dr Chamila Gunasekara from RMIT University is currently engaging with partners including Textile Recyclers Australia, carpet manufacturer Godfrey Hirst and councils in Victoria to conduct field studies of on-ground slabs made of reclaimed textiles.
- The latest results were published in the Construction and Building Materials journal.
- This research addresses a major challenge in the construction sector, as the annual cost of repair for cracks in reinforced concrete structures in Australia is about A$8 billion. In the US, the cost is estimated at US$76 billion per year.
CONCRETISING FURTHER: With state-of-the-art textile research facilities at RMIT, the team of civil engineers and textile researchers has also been able to use other discarded textiles including clothing fabrics to make concrete stronger.
- Cracking in early-age concrete slabs is a long-standing challenge in construction projects that can cause premature corrosion, not only making a building look bad but also risking its structural integrity and safety. Scrap carpet fibres can be used to increase concrete’s strength by 40% in tension and prevent early cracking, by reducing shrinkage substantially.
THE WASTE CHALLENGE: Australia is the second largest consumer of textiles per person in the world, after the US. The average Australian purchases 27kg of new clothing and textiles every year, and discards 23kg into landfill.
- The disposal of carpets, firefighting clothes and other textiles including discarded fabrics poses an enormous environmental challenge.
- Burning carpet waste releases various toxic gases, creating environmental concerns.
- Firefighting clothes waste also poses a challenge, as the same qualities that made these materials ideal for firefighting also made them difficult to recycle.
- Up to 70% of textile waste would be suitable for conversion into usable fibres, presenting an opportunity in the materials supply chain.
FIELD TRIALS conducted with support from industry and local government partners will help capture the unexpected conditions encountered in real-world construction projects.
- The ARC Industrial Transformation Research Hub for Transformation of Reclaimed Waste Resources to Engineered Materials and Solutions for a Circular Economy (TREMS) and an early-career research grant will fund the field trials as well as computational modelling.
- TREMS is led by Professor Sujeeva Setunge from RMIT.
- The team is collaborating with Professor Andrzej Cwirzen from the Luleå University of Technology in Sweden on computational modelling.
