Buildings that eat their veggies are stronger and greener
Cameron Jewell | 18 June 2018
They say eating your veggies makes you stronger, but scientists have found they also make our buildings stronger, and greener.
University of Lancaster researchers found that adding “nanoplatelets” extracted from the fibres of root vegetables such as carrots and sugar beets led to stronger, more sustainable concrete.
The nanoplatelets work by increasing the amount of calcium silicate hydrate, which the researchers said “controls the performance of concrete”. They also stop the concrete from cracking. The vegetable-based cement had a denser “microstructure”, helping to prevent corrosion and improve lifespan.
The outcome is a lesser amount of cement needed to make concrete. Proof-of-concept studies showed that adding the root vegetable nanoplatelets could reduce the amount of cement needed per cubic metre of concrete by 40 kilograms, with a concomitant reduction in CO2 of 40kg.
The vegetable-based additives also outperformed other commercially available cement additives – such as graphene and carbon nanotubes – but at a much lower cost.
As well as mechanical and sustainability improvements, the use of root vegetables could tackle food waste.
“These novel cement nanocomposites are made by combining ordinary Portland cement with nanoplatelets extracted from waste root vegetables taken from the food industry,” lead researcher and engineering professor Mohamed Saafi said.
“The composites are not only superior to current cement products in terms of mechanical and microstructure properties, but also use smaller amounts of cement. This significantly reduces both the energy consumption and CO2 emissions associated with cement manufacturing.”
The team is now working with industrial partners at Cellucomp – which already uses the nanoplatelets to make more durable paints – to further research the new technology, which has been supported by £195,000 (AU$348,000) from the European Commission’s Horizon 2020 program.
The project is also looking at whether existing cement structures could be reinforced with nanofibre-based sheets made from the vegetable nanoplatelets, which the researchers believe may outperform existing alternatives, such as carbon fibre, due to a better ability to bend and withstand damaging forces.