New cement crucial to solving Britain’s construction crisis

Dr Moray Newlands, from Dundee’s School of Science and Engineering, has warned that a supply chain crisis has further prompted an urgent need for the sector to build for the future and meet net zero targets.

He will lead a team of researchers that will test the performance characteristics of a new blend of cement utilising calcined clay, an alternative to fly ash and ground-granulated blast furnace slag (GGBS) that are currently used as supplements in much of the country’s cement. It is part of a £1.4 million research project led by the Mineral Products Association and funded by UK Research and Innovation’s Transforming Foundation Industries programme.

With fly ash and GGBS becoming increasingly scarce and produced at a significant cost to the environment, Dr Newlands believes that finding a new, sustainable formula for UK cement is crucial to ensure the long-term prosperity of the sector.

“Low carbon cement and concrete in this country is heavily dependent on fly ash and GGBS,” he said.

“However, as well as a need to make the construction industry more sustainable, there are also long-standing supply chain issues with these materials.

“Calcined clay is a material that has the potential to address these concerns, and is already prevalent in mainland Europe, but we know very little about UK clay and whether it will perform to the standards that are required for construction projects.

“Demand for construction materials has been strong throughout the pandemic, but with an increasing focus on the industry’s environmental impact it is important that we examine ways to make it more sustainable. If there is a failure to adapt, then there is a real risk that demand for cement will outstrip supply.”

Bruce Adderley, director of UKRI’s Transforming Foundation Industries challenge, said, “Collaboration is the lynchpin for innovation across these industries, as the opportunities for mutual benefits, re-use of by-products and the exchange of knowledge and skills will be essential for ensuring their journey towards improving their efficiency and productivity to meet new market challenges.

“We have seen from the quality of applications just how new processes and a commitment to combined thinking can work together to address some of the key issues affecting the sector. The understanding of how waste derived clay materials arising from the production of ceramics can create added value for other foundation industry markets would make a significant impact in resource efficiency for the cement, concrete, ceramics and brick industries, but also secure a sustainable feedstock for the future which is not dependent upon increasingly scarce materials.”

The Dundee team will test the integrity of the calcined clay concretes, using state-of-the-art technology to ensure that it meets rigorous industry standards.

Fly ash has been a staple ingredient in concrete, increasing its strength and durability. However, as a by-product of coal, its supply has become increasingly scarce as the number of coal-fired power stations diminish. Similarly, the reduction in blast furnace operations in the UK has decreased in the amount of GGBS available for construction, prompting the need for new, more sustainable alternatives.

While supplies of clay are sustainable and prevalent throughout the UK, little is currently known of calcined clay’s performance characteristics in concrete.

“Around 30% of cement in UK concretes will consist of fly ash or GBBS, so our study of UK calcined clay is hugely significant for the construction industry in this country,” added Dr Newlands.

“The facilities we have here in Dundee are second to none and we have a long track record of carrying out this kind of research. By the time we have analysed the samples we will have a much clearer idea of what kind of role calcined clay can play in future construction projects in this country.”