A new low-emission concrete, with the potential to transform the global construction sector, recently made its commercial debut at a former train depot site in Manchester.
It was while attending an ICE Manchester branch knowledge event that a spark was first ignited for me, leading to a key role in the development of a recipe for a more sustainable concrete alternative.
The lecture was held at the University of Manchester’s UMIST campus, in the very same building where I studied civil engineering some 20 years ago. Although it was early days, it was here that I first heard of the potential for graphene to structurally enhance concrete.
Together with Rob Hibberd, we formed Nationwide Engineering and went on to work in partnership with the Graphene Engineering Innovation Centre (GEIC) and continue to do so with many more years of development ahead of us.
Better than traditional concrete
Known as Concretene, the product uses graphene, a revolutionary 2D material, to significantly improve the mechanical performance of concrete, allowing for reductions in the amount of material used and the need for steel reinforcement.
This can reduce CO2 emissions by up to 30%, while at the same time driving down costs, making Concretene a greener and cheaper solution.
First commercial use
The product has recently been used to create a new 54x14-metre mezzanine floor, set to become a roller disco on part of the vast £1.5bn Mayfield regeneration site in Manchester.
The installation is the first commercial use of Concretene in a suspended slab, as used in high-rise developments. This marks an important step towards testing and developing it as a widely used building material, allowing it to be used as a substitute for concrete on an industrial scale.
What is traditional concrete's problem?
Production of cement for concrete in the building industry is one of the leading causes of global carbon dioxide emissions. In fact, if concrete was a country, it would be the third largest emitter in the world behind only China and the US, producing around 8% of global CO2 emissions.
Less material, less time
Concretene has great potential to address the construction industry’s need to lower emissions, by reducing the amount of concrete required in construction projects by as much as 30%. It also offers efficiency savings by slashing drying time - pours of Concretene to date have achieved the equivalent of 28-day strength in just 12 hours.
Liquid concrete sets into its solid form through chemical reactions known as hydration and gelation, where the water and cement in the mixture react to form a paste that then dries and hardens over time.
Graphene makes a difference by acting as a mechanical support and as a catalyst surface for the initial hydration reaction, leading to better bonding at microscopic scale and giving the finished product improved strength, durability and corrosion resistance.
The use of graphene in concrete produces 6.3kg of CO2 per tonne of concrete - a 21.94kg reduction per tonne compared to traditional steel reinforcement.
The total estimated reduction in CO2 emissions for the Mayfield Depot slab compared to a traditional concrete solution is 4,265kg.
What could this mean for the future?
The international building industry has already shown wide interest in Concretene as a means of achieving significant carbon reductions in construction.
Crucially, Concretene can be used just like standard concrete, meaning no new equipment or training is needed in the batching or laying process, and cost-savings can be passed directly to the client.
Nationwide Engineering has three existing five-year construction frameworks with Network Rail and two seven-year Government Crown commercial building frameworks.
With Network Rail committing to an 11% reduction in CO2 emissions over the next four years, graphene-enhanced concrete shows significant potential to help meet this target. Rolled out across the global building industry supply chain, the technology has the potential to shave 2% off worldwide emissions.