Had one asked Franz-Josef Ulm 10 years ago if a concrete bridge could be designed from atomic models, he might have said, "Come on, get real." Today, scientists working under Ulm's direction at the Massachusetts Institute of Technology are busy cracking concrete's molecular code.
Now in its fourth year, MIT's Concrete Sustainability Hub grew out of a handful of experts Ulm dubbed the Liquid Stone Gang. Now roughly 40 people strong, the team has expanded its research beyond concrete's role in construction to deepwater oil drilling, shale extraction, blast resistance and other applications.
An engineer and professor, Ulm, 48, has been obsessed with the unusual properties of concrete—a material that turns from a liquid to a solid at room temperature—since childhood. "Concrete was part of my upbringing," says Ulm in a thick Bavarian accent. Back home in Germany, his mother is still a practicing civil engineer, having just celebrated her 50th anniversary in the profession.
Ulm's mechanical knowledge has helped the hub apply what he calls "dirty physics" to a material that has been used for centuries but little understood. One team member, Roland Pellenq, in 2009 became the first to build an atomic model of portland cement, concrete's main ingredient. "Here is a team which has not ever been assembled before," says Hamlin Jennings, a cement scientist and hub executive director. "It was Franz who put the team together—that's a big vision."
In fall 2012, the hub released new research that sheds light on how cars and trucks interact with U.S. highways. Scientists concluded that poorly built and maintained roads can lead to 3% more fuel consumption and carbon emissions than roads designed for sustainability.
"By keeping pavement in good shape, you spare the user a cost, and on a larger scale, you reduce the environmental footprint of our pavement system," says Ulm. "So, really, it is about what mileage we are getting out of our pavement."
Previously, the hub, which is funded by cement groups, released controversial research analyzing the life-cycle costs of concrete in buildings and roads. It also is studying cements that can achieve high strengths with less embedded carbon.