Davide Zampini

Davide Zampini, Cemex’s vice president of global R&D on the two key ingredients for ultra low-carbon concrete: chemistry and people. Thirty years ago, as a freshman at Northwestern University in Chicago, Davide Zampini was all set to study medicine. Then he walked into the office of legendary materials scientist Hamlin Jennings.

“It was my first day and he was my counsellor. He said, ‘If you ever wanted a challenge in your life, you would study the chemistry of cement. Millions of cubic metres are used worldwide, but to this day, no one has cracked the science.’”

Zampini was hooked. He ended up devoting his studies and his career to understanding concrete at the deepest molecular level. For the last 17 years, he has been head of global R&D at cement giant Cemex. Startlingly, he believes that for all the progress in making stronger concrete and lowering embodied carbon, there are even more unknowns today.

“Five years ago, the majority of cements being sold were ordinary Portland cement, consisting predominantly of clinker. Now, we’re talking about cements with a clinker factor of 50%, which means that other constituents are playing an important role. We’re going to another level of complexity.

There are very bright people putting the puzzle together, but there’s an additional dimension that’s never been looked at.” Zampini is responsible for around 50 of those people, based mainly in Switzerland and Mexico – a small team in the context of Cemex’s 40,000-strong global workforce. “Sometimes it’s not how big your team is, it’s the talent pool and how innovation is managed to fit the company’s strategy. We don’t have infinite resources, so we have to be very creative, very efficient and very focused.”

His job is essentially to think radically and disrupt his own industry from within, while remaining hard-nosed about the economics. “Making ends meet” is how he describes this mission. “When I look at our research activities, be it decarbonisation or developing new products or manufacturing processes, it’s really making sure that the things we’re altering work when they get to the concrete, not just in terms of strength and how it looks in the building, but also the fresh properties.

Because in the end, the concrete is the product that faces the market, and the market is pretty demanding. “The bottom line is to be continuously curious, open to everything that’s coming out, but to assess it critically – or we’re not doing the industry any favours. Sometimes you see startups coming up with great ideas, but the business case will never fly because they’re trying to sell limestone for 900 times more than today.”

His team’s work spans the value chain, from manufacture to design to delivery. “For the future, I think the key word is integration, and being knowledgeable about how to put different technologies together and have them align and work in synergy. There’s not going to be a single panacea.”

Digitalisation will be important, he says – Cemex has just launched BIM Concrete Studio, a free set of design tools that can plug into any building information model (BIM) to analyse embodied carbon at element and material level throughout a project. He also thinks artificial intelligence could help to finally crack how concrete constituents interact at a molecular level.

After all these years, it’s still chemistry that excites Zampini most. He sees great potential in admixtures, chemicals added in small quantities that change the properties or behaviour of a mix. “Admixtures are an enabler of all the concrete technologies that we see, or what we can achieve in terms of super-reductions. We’re really only scratching the surface.” Imagine if we could triple the strength of cement tomorrow, he adds – that could allow far higher rates of substitution, and correspondingly large drops in embodied carbon.

Cemex’s official 2030 target is to produce cementitious material with an embodied carbon below 430kgCO2e/tonne, down 47% on the 1990 baseline and 31% on 2020. But Zampini thinks it could go as low as 200kgCO2e/tonne. “There’s a lot of conventional wisdom about how clinker is manufactured. I’m a very firm believer that we can completely revisit clinker chemistry, and how clinker is manufactured, to produce it at very low emissions. Who’s to say that what we call concrete today is going to be what we call concrete in the future?

One way to think of it is like, what if trees underwent a radical genetic transformation. It still looks like a tree outside, but maybe the way it intakes water or the leaf structures are completely different. The concrete that you cast 30 years from now may look exactly the same, but everything inside could be completely different.”

But to transform clinker chemistry, you have to really understand it. That’s why the other part of his mission is to get young people excited about the future of concrete, and inspire them to study it at university. “Just seeing that there’s a problem isn’t enough. You need the insight to know how to tackle it.

I was very fortunate because I studied under great cement chemists and concrete technologists who could really articulate the problems to be solved. Civil engineering and materials science departments are seeing numbers dwindle. That’s a problem because you need to attract the talent base to generate those radical, innovative ideas.” He recently got chatting to some young guys working in a store in Chicago.

“They were studying architecture. I started showing them videos of the stuff that we do with concrete, and they were like, ‘Woah, that’s really interesting. Can we get a copy, can we contact you?’ I think everyone in the sector should see themselves as having that responsibility. There’s still so much to be to be done. But I think the first thing is to get young people excited about it.”

Interview by Katie Puckett

Photos Paul Burroughs