The Future of Concrete
Watch the episode on YouTube right here!
Thinking about concrete as a sustainable material might sound a bit weird. But when you look past the headline statistics regarding its carbon impact, you start to see a material that is undergoing a quiet, chemical revolution.
We recently explored this topic with Andrea Charlson, a Senior Sustainability Specialist and Circular Economy Lead at The Concrete Centre in the UK. With a career spanning major infrastructure projects and strategic policy roles, Andrea brings a wealth of experience to the conversation about how concrete is evolving to meet a net-zero future.
In the following article, we’ll discuss:
- More Than a Product: A Recipe for Change
- The Decarbonization Roadmap
- Circular Economy: Keeping Value in Use
- Overcoming the “Risk” Barrier
More Than a Product: A Recipe for Change
Concrete is often viewed as a static, “dirty” material that we should simply remove from the industry. However, Andrea points out that concrete is not a single product—it is a recipe with variable proportions. While a concrete block might look the same as it did 40 years ago, its internal chemistry has in fact changed.
In the UK alone, the cement and concrete industry have already reduced its carbon footprint by 63% since 1990. This has been achieved through a combination of:
- Waste fuels used to generate the high heat required for clinker production.
- Supplementary Cementitious Materials (SCMs) like Ground Granulated Blast Furnace Slag (GGBS) and pulverized fly ash.
- Increased efficiency in manufacturing and placing technologies.
The Decarbonization Roadmap
As the industries that provide traditional byproducts like GGBS (steel) and fly ash (coal) phase out, the concrete industry is diversifying its “menu”. The future of low-carbon concrete lies in bespoke mixes tailored for specific applications—whether it’s a foundation, a slab, or a column.
Andrea highlights emerging innovations that are moving into standard practice, such as calcined clay and limestone fines, which can significantly reduce the requirement for Portland cement (CO2-intensive clinker). The goal is to move away from simply specifying a material and instead specifying a carbon performance band (A to F), allowing producers to optimize the mix locally.
Circular Economy: Keeping Value in Use
While CO2 reduction is critical, Andrea emphasizes that the circular economy is the other half of the sustainability story. Concrete’s greatest environmental asset is its durability; the highest level of circularity is keeping a structure in use for as long as possible.
Concrete’s circular lifecycle includes:
- Adaptability: Concrete frame buildings are frequently refurbished and rejuvenated, giving them a new lease on life rather than being demolished.
- Recyclability: Concrete is 100% recyclable. In the UK, over 90% of recovered concrete is recycled into aggregate, primarily for fill.
- Innovative Recovery: New technologies are allowing engineers to cut out segments of in-situ concrete for reuse in new applications, effectively treating old buildings as “material banks” – urban mining.
Overcoming the “Risk” Barrier
For many structural engineers, the primary challenge to adopting “green” concrete is the risk profile. Choosing a non-standardized mix or reused components involves a perceived technical risk that can be a deterrent.
However, Andrea has seen the opposite: Engineers welcoming the reuse of concrete for structural purposes. With great success.
Concrete is here to stay, but the way we use it is changing. For professionals across the industry, the message is clear: the future isn’t about removing concrete, but about optimizing the recipe for a circular, low-carbon world.