Electric concrete melts snow & improves road safety

28th January 2016

Nat Bowers

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Chris Tuan, Professor of Civil Engineering, University of Nebraska-Lincoln, has added steel shavings and carbon particles to a standard concrete mixture, allowing it to conduct enough electricity to melt ice and snow in the worst winter storms while remaining safe to the touch.

Tuan's research team is demonstrating the concrete's de-icing performance to the Federal Aviation Administration during a testing phase that runs through March 2016. If the FAA is satisfied with the results, Tuan said the administration will consider scaling up the tests by integrating the technology into the tarmac of a major U.S. airport.

Tuan commented: "To my surprise, they don't want to use it for the runways. What they need is the tarmac around the gated areas cleared, because they have so many carts to unload (i.e., luggage service, food service, trash service, fuel service etc.) that all need to get into those areas. They said that if we can heat that kind of tarmac, then there would be (far fewer) weather-related delays. We're very optimistic."

In 2002, Tuan and the Nebraska Department of Roads tested the idea years ago on the 150ft Roca Spur Bridge, making it the world's first to incorporate conductive concrete. Inlaid with 52 conductive slabs that have successfully de-iced its surface for more than a decade, the bridge exemplifies the sort of targeted site that Tuan envisions for the technology.

"Bridges always freeze up first, because they're exposed to the elements on top and bottom. It's not cost-effective to build entire roadways using conductive concrete, but you can use it at certain locations where you always get ice or have potholes," added Tuan.

Potholes often originate from the liberal use of salt or de-icing chemicals that can corrode concrete and contaminate groundwater over time, making the conductive concrete an appealing alternative with lower operating and maintenance costs. The power required to thermally de-ice the Roca Spur Bridge during a three-day storm typically costs about $250 - several times less than a truckload of chemicals, he said.

Tuan developed the concrete with the assistance of Lim Nguyen, associate professor of electrical and computer engineering; Bing Chen, professor of electrical and computer engineering; and Sherif Yehia, a professor at the American University of Sharjah who earned his doctorate in civil engineering at UNL. The FAA is currently funding the team's research, which also received past support from the Nebraska Department of Roads.