Ancient Concrete-Making Can Help Mitigate Climate Change

Admir Masic, an associate professor at MIT’s (Massachusetts Institute of Technology) Department of Civil and Environmental Engineering, studies ancient materials whose secrets he believes have the potential to solve some of the modern world’s most pressing problems while working to solve modern-day problems.

“We’re leading this concept of paleo-inspired design: that there are some ideas behind these ancient materials that are useful today,” Masic says. “We should think of these materials as a source of valuable information that we can try to translate to today. These concepts can revolutionize how we think about these materials” (Winn, 2024).

Masic is referring to Roman concrete. Not only is this material ultra-durable – their remains have survived for two thousand years, but they also have self-healing properties, which allow it to constantly heal itself, which is something that Masic finds fascinating and wants to explore more to hopefully use to improve on how things are done today.

Although Masic now loves his work at MIT, where he says he could be himself and research subjects he is passionate about, his background is not as glamorous. As a teenager, he and his parents fled war-torn Yugoslavia and sought refuge in Northern Croatia. At the refugee camp, Masic discovered his natural gift in Chemistry and nurtured this ability, winning one chemistry competition after another. This led him out of the country and ultimately landed him at MIT. 

At MIT, he also started the MIT Refugee Action Hub (now MIT Emerging Talent) to provide educational opportunities to students displaced by war. It also led him to study ancient materials that he believes can solve our problems today, such as climate change.

Masic has become an expert in Raman spectroscopy, a relatively new approach to studying cement, which he used to examine the self-healing properties of Roman concrete. He uses Raman spectroscopy to characterize materials in the cement. He applies it to explore how cement could store carbon dioxide and act as an energy-storing supercapacitor. He has also solved ancient mysteries about the lasting strength of ancient Roman concrete, with lessons for today’s $400 billion cement industry.

The aim is not to replace Portland cement, which has set the standard to produce modern concrete and has since been used and produced in vast quantities to build and construct our infrastructure and society, but to introduce new functionalities into concrete to make it more sustainable and less carbon-intensive.

MIT’s Admir Masic, a team from Harvard University, and laboratories in Italy and Switzerland have made progress in discovering ancient concrete manufacturing strategies that incorporated several key self-healing functionalities. They found that the hot mixing approach in making this ancient concrete was the key to its super-durable nature.

“The benefits of hot mixing are twofold,” Masic says. “First, when the overall concrete is heated to high temperatures, it allows chemistries that are not possible if you only used slaked lime, producing high-temperature-associated compounds that would not otherwise form. Second, this increased temperature significantly reduces curing and setting times since all the reactions are accelerated, allowing for much faster construction” (Chandler, 2023).

Their findings are published in the Science Advances Journals – Hot Mixing: Mechanistic Insights into the Durability of Ancient Roman Concrete.

The study hopes that the longer functional lifespan and development of lighter-weight concrete could help reduce the environmental impact of cement production, which currently accounts for about 8% of the world’s GHG emissions.

Masic’s labs also focus on other new formulations to make concrete absorb CO2 from the atmosphere, which could help reduce the concrete’s climate impact.