Big news for concrete fans: Scientists have figured out how to quadruple the lifespan of elaborate building materials – and privacy was all over our blood. In a study published last week in Applied Materials Today, researchers at Worcester Polytechnic Institute explained how they took inspiration from the human body to develop their new concrete. The result, they say, is a building material that can “heal” cracks in the same way that our bodies can heal cuts or scratches.
“It sounds scientific, but it’s a real solution to a significant problem in the construction industry,” says lead author Nima Rahbar. Now, there’s a reasonable chance that when you see the word “concrete”, your response is less “Oh, interesting, please continue!” And more “oh, yes, concrete, gray things that made a bunch of weird architecture possible”. This is not fair, however, because concrete is attractive: it is the most widely used substance on the planet, and by some estimates it now exceeds the combined mass of every tree, shrub, and shrub in the world.
As the use of concrete increases worldwide, so does the industry’s devastating environmental impact. Concrete production is now responsible for one-tenth of global greenhouse gases – in other words, if concrete were a country, it was second only to China and the United States in CO2 emissions. One of the major reasons for this huge environmental cost is that concrete does not last that long. Until we figure out what made Parthenon so durable, our modern cement structures will continue to crack and deteriorate in less than a decade. More cracks means more cement is needed to fill these cracks, and therefore more damage to the environment.
“The global use of concrete is ubiquitous,” Rahbar explained. “If small cracks can be repaired automatically after first starting, they will not become major problems that need to be repaired or replaced.” This new development is certainly a huge step in the right direction. It’s not the first type of self-healing concrete we’ve seen, but the team believes it has many advantages over other, mostly bacterial-based, methods. It is “significantly faster”, the paper notes, capable of closing millimeter-scale cracks in just 24 hours – current methods explain it, it takes a minimum of four weeks to do so.
