A group of engineers is replacing sand with coffee grinds in a new twist on concrete.
The project is – fittingly – in Melbourne and is among the work being celebrated at RMIT’s EnGenius event, where more than 1000 final-year engineering students from 11 disciplines showcase their work to industry and the public.
The group found they could replace up to 10 per cent of sand in a concrete mix with coffee grounds and have produced sample ‘coffee bricks’.
It is a novel solution to reduce the amount of coffee grinds going to landfill and reducing the environmental impact of industry’s demand for sand.
There were an estimated 2600 cafes in the City of Melbourne alone in 2017, producing about 156,000kg of coffee-ground waste every month.
Bachelor of Engineering (Civil and Infrastructure) (Honours) students Senura Kohombange and Anthony Abiad worked with School of Engineering senior lecturer Dr Srikanth Venkatesan to test and develop the ‘coffee bricks’.
“It seems fitting then that we’re working on this project in Melbourne, a city known for its great coffee culture,” Mr Kohombange said.
“We are very excited to present the project, share the idea with others and showcase how some innovative thinking can turn a waste product into an everyday construction material.”
Mr Venkatesan said the biggest challenge was ensuring the addition of spent coffee grinds did not lead to a reduction in strength of concrete.
This would be the focus of further testing and development to make this product viable for use in real-world applications, he said.