It’s a beautifully simple concept, really. The new kind of concrete still cracks, but the fissures are much smaller. After the next few times it rains, the combination of the moisture and carbon dioxide reacts with the concrete, healing the cracks with the resulting calcium carbonate. Victor Li is the innovator behind this new “engineered cement composite”, or ECC, and has been working on it for the past fifteen years. Li’s concrete is more flexible than other materials on the market, so its average crack width is a mere 60 micrometers (only half as wide as a human hair!). This allows for full healing and a much stronger, more durable concrete in general.
Li also spells out his commitment to green building saying that “rebuilding with [ECC] would allow a more harmonious relationship between the built and natural environments by reducing the energy and carbon footprints of these infrastructure. As civil and environmental engineers, we are stewards of these mega-systems. Advanced materials technology is one means to keep them healthy.”
Now for another exciting tidbit: this calcium carbonate is the same stuff that creates the mineral deposits in caves! Stalactites, stalagmites, flowstone? All calcium carbonate. The milky white tracings running down concrete and brick buildings? Same thing. As a cave tour guide, artist, and writer for a masonry company, it’s rare that I find something with a direct connection to all three! Thanks for letting me gush a little about this, and check out some of my favorite calcite creations: