Carpet combats cracking
Carpet fibres could make concrete more robust.
Engineers in Australia have introduced a new method to produce stronger, crack-resistant concrete using scrap carpet fibres, potentially improving the material and boosting sustainability in construction.
The research, conducted by RMIT University, uses waste carpet materials to address early-age shrinkage cracking - a persistent issue in construction that requires substantial repair costs.
The research team, led by Dr Chamila Gunasekara from RMIT University, has demonstrated that incorporating carpet fibres into concrete reduces shrinkage cracking by up to 30 per cent and improves tensile strength by 40 per cent.
This method enhances durability and addresses environmental challenges posed by textile waste.
“We have developed a technique using waste carpet fibres to reduce early-age shrinkage cracking … while also improving the concrete’s durability,” said Dr Gunasekara.
The researchers have partnered with organisations such as Textile Recyclers Australia and Godfrey Hirst Australia, alongside Victorian councils, to carry out field trials of concrete slabs reinforced with reclaimed textiles.
The trials aim to evaluate the performance of this sustainable concrete under real-world conditions.
Cracking in reinforced concrete structures is a costly issue, with Australia spending approximately AU$8 billion annually on repairs. In the United States, this figure is close to US$76 billion.
The research also tackles the environmental problem of discarded textiles.
Dr Gunasekara says Australia is one of the largest per-capita consumers of textiles globally, with an average of 23 kilograms of textile waste per person ending up in landfill each year.
“Burning carpet waste releases various toxic gases, creating environmental concerns,” he added.
The team is exploring the use of other waste textiles, such as discarded clothing, to enhance concrete performance. According to laboratory tests, concrete incorporating these materials meets Australian engineering and environmental standards.
Dr Shadi Houshyar, a textile and material scientist at RMIT, said the methods have the potential to repurpose 70 per cent of textile waste.
The research has been published in the Construction and Building Materials journal, with detailed findings revealing that specific fibre types, such as nylon and polypropylene, optimise both strength and shrinkage performance.