Almost everyone knows that vegetables are good for the health of humans. A new study has shown that they could also play a vital role in the construction of stronger and greener buildings.
Engineers from the Lancaster University have collaborated with industrial partners at Cellucomp Ltd UK to study the means to strengthen concrete mixtures and to make them more eco-friendly by the addition of “nano platelets” derived from the fibers of root vegetables.
The study has received support of £195,000 from the European Union’s Horizon 2020 funding and will build on outcomes of previous tests that have shown that concrete mixtures that include nano platelets from carrot or sugar beet considerably enhance the mechanical properties of concrete.
It was also discovered that the vegetable-composite concretes outperformed all the cement additives available in the market (for example, carbon nanotubes and graphene) at a considerably lower cost.
The root vegetable nano platelets have two-way functionality: they increase the amount of calcium silicate hydrate (the main substance controlling concrete performance) as well as prevent the formation of cracks in concrete.
Since the concrete performance is increased, lesser amounts are required in construction.
At present, the construction industry is emergently looking for ways to restrict its carbon emissions. When ordinary Portland cement (one of the principal ingredients for concrete) is produced, a higher amount of carbon is emitted - its production constitutes 8% of total CO2 emissions worldwide. Studies predict that this figure will increase by two times in the next three decades owing to increasing requirements.
This proof-of-concept research demonstrated that when the root vegetable nano platelets were added, 40 kg of ordinary Portland cement was saved per cubic meter of concrete - which relates to a saving of 40 kg of CO2 for the same volume. This is because the increased strength of the root vegetable mixture decreases the concrete sections required in buildings.
According to Professor Mohamed Saafi, lead researcher from Lancaster University’s Engineering Department, root vegetable concrete can be highly successful in minimizing the construction of carbon emissions.
These novel cement nanocomposites are made by combining ordinary Portland cement with nano platelets extracted from waste root vegetables taken from the food industry.
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.
Professor Mohamed Saafi, Lead Researcher
It was also found that the vegetable-based cementitious composites had a denser microstructure, which is vital to prevent corrosion and to increase the service life of the materials.
Also part of the research agenda is the addition of very thin sheets made of vegetable nano platelets to prevalent concrete structures to fortify their strength. The scientists are hopeful that the vegetable nanofiber-based sheets will outshine prevalent substitutes, such as carbon fiber. This is partially due to the fact that concrete beams fortified with the sheets can bend more, thereby helping deflect potentially damaging forces.
The two-year project will examine the science behind the outcomes of the proof-of-concept studies to gain a complete knowledge of the way in which vegetable nano platelet fibers improve the concrete mix. The scientists will also endeavor to enhance the concrete performance to help make a mixture that can be used in the construction industry.
Cellucomp Ltd has already been using root vegetable fibers to produce more durable paints.
According to Dr. Eric Whale from Cellucomp Ltd, “We are excited to be continuing our collaboration with Professor Saafi and developing new applications for our materials, where we can bring environmental and performance benefits.”
Video credit: Lancaster University