Pete Buttigieg, secretary of the U.S. Department of Transportation, recently helped moderate a session at the Transportation Research Board’s 2024 Annual Meeting in Washington D.C. regarding the development of new infrastructure materials to help “reinvent” roadways, airport runways, and railroad networks.
“Our aim is to make infrastructure materials like [road] pavement more effective, resilient, durable, and longer lasting than ever before,” Buttigieg explained. “It’s about making the right kind of investments not just to rebuild our nation’s infrastructure but to redefine how it is built.” He added that while only 60 years separated the first airborne flight at Kitty Hawk, N.C., and America putting a man on the moon, the transportation industry still relies on infrastructure materials in use during the Roman Empire.
“Our role, then, at USDOT, is to make sure we have a good understanding of the role of materials we use in transportation and how they are encoded into the decisions we make,” the secretary said. “There is a very low level of attention paid to materials research, but an even marginal change in quality could be massive if multiplied out among all the projects we work on. There are things literally going on under our noses that could provide so much opportunity for us in terms of providing materials with intelligence, more durability, and sustainability. I urge you to continue this work. Really, in the grand scale of things, this is not just money-saving research but lifesaving as well. Do not let anyone tell you materials are not glamorous.”
The session – also moderated in part by Dr. Robert Hampshire, USDOT deputy assistant secretary for research – covered a wide range of topics with speakers from across the public and private sectors.
Dr. Matthew Pava, program manager for the Biological Technologies Office at the Defense Advanced Research Projects Agency, talked about his unit’s ongoing development work into formulating “self-healing” concrete. That endeavor – under the “Bio-inspired Restoration of Aged Concrete Edifices” or “BRACE” program – aims to prolong the serviceability of Department of Defense structures and airfield pavements by integrating a self-repair capability into existing concrete through the addition of biological components, such as bacteria, that would flow through cracks in concrete much like blood vessels, filling them in along the way.
Professor Franz-Josef Ulm from the Massachusetts Institute of Technology discussed how he is looking into adding carbon black to roadway pavement so the pavement itself can both transmit and store electrical power – power that could then recharge electric vehicles as they travel up and down the road. “It is about creating electro-magnetic conduction through the roadway network established by the USDOT,” he explained. “This would create an electric field around the roadway – and if the frequency is high enough, it could charge the electric vehicle as it is moving. [That electrical power] could also get rid of snow and ice via heating up of the pavement.”
Tadeu Carnerio, CEO of Boston Metal, explained how his company seeks to use electricity instead of blast furnaces to make steel – eliminating thousands of tons of carbon emission in the process. That electrical-based forging process could also be used to extract ore from mining waste and convert it into “high value” metals such as chromium; thus creating a domestic supply of a material currently largely imported into the U.S.
Cooper Rinzler with Breakthrough Energy Ventures – a private sector financing firm founded by Microsoft’s founder Bill Gates – discussed how his company is enabling a “financial pathway” for novel strategies and materials that will help reduce carbon emissions globally.
“Cement and steel are the foundations of our civilization – they are cheap, they are everywhere, and we have hundreds if not thousands years of data on them,” Rinzler explained. “Most of the carbon emissions are from the processing of those materials, so we are looking at ways we can recycle and reuse them, as well as de-carbonize their production processes.”
Maggie Kwan, senior vice president-civil and structural engineering for AECOM Tishman, talked about how efforts in her sector to make “vertical” construction processes and materials “greener” and longer-lasting could also be applied to the “horizontal” construction needs of roads, tunnels, and bridges. “For example, our sector has developed ‘green’ concrete guidelines – it is a roadmap for the highest concrete standard with zero added costs,” she explained. “It is all part of the balancing act, the economics – everything must be balanced, not to one side or the other; not affecting cost or strength or deflection properties of the steel and concrete we use in our skyscrapers.”
And it is that crucial “balancing act” that Mostafa “Moe” Jamshidi, deputy director of operations for the Nebraska Department of Transportation, addressed in his comments at the session. “Our challenge is to take all of this good work and put into practice,” he explained. “State DOTs are open to innovation – but it must be scalable, practicable, and it must be safe. If we can achieve those conditions, then we are ready to go to work and make it happen.”
Jamshidi, who received the Thomas H. MacDonald Memorial Award at the American Association of State Highway and Transportation Officials 2023 Annual Meeting for his many contributions to the state DOT community, said state DOTs develop materials specifications around five key factors: “They must be durable, easy to use, readily available, and predictable – and all at a reasonable cost,” he said. That can get complicated when a variety of different innovations come into play. “Here at this session, you’ve heard about one guy putting bacteria into concrete and another electrifying it for electric vehicles; now we as a state DOT must write a specification so a contractor can do both of them,” he pointed out.
Jamshidi also emphasized that transportation infrastructure is “not a dumping ground” for waste materials. “We have to engineer these materials so that they last long enough that we don’t have to replace them too early,” he stressed. “We also want a history of its performance and know what we can count on with it. That’s why you need to make sure that when you bring new materials to us, that you do your homework and do it right. That’s why it is important to engage with state DOTs early in the development of these new materials.” Information courtesy of AASHTO. Learn more here.