As climate change affects more people around the world, professors at the University of Missouri are looking into ways to make roads more sustainable by recycling rubber.
A group of University of Missouri Civil Engineering professors are developing environmental production declarations, or EPDs for rubber-modified roads. These EPDs function as labels, which can give government officials more information when buying asphalt – beyond just cost.
Dr. Punya Rath, a researcher on the project, said they are examining the greenhouse gas production of rubber-modified asphalt, which is being used in different road projects across the country.
Rath said EPDs are like nutrition labels and would display the amount of emissions of various greenhouse gasses, such as carbon dioxide that were released when making the asphalt.
“So, at each step there's CO2 and different gasses that are associated with different kinds of fuel usage and different kinds of machinery usage,” Rath said.
Rath said government officials have traditionally selected asphalt based on cost effectiveness, but these new labels would give them more information about environmental impact – ideally leading to more informed decisions when purchasing asphalt.
According to the researchers, there will also be a way to subtract carbon dioxide from the calculation, similar to carbon credits, when formulating the environmental labels.
For example, if a company cuts down a tree and then replants the tree – that can be subtracted from the total environmental impact on the EPD label.
Bill Buttlar is another MU Civil and Environmental Engineering working on the project, and has been testing Rubber roads here in Columbia.
Buttlar said in 2021, Stadium Boulevard got a thin overlay of rubber-modified asphalt, and,so far, it has performed better than or matched the non-recycled asphalt equivalent.
“When you put that in asphalt it imparts that same sort of life extension,” Buttlar said. “Not only extending the life of the asphalt. It's during that life it stays smoother.”
In the lab, Buttlar has been testing different mixtures of rubber-modified asphalt to see which ones are the most durable, and testing how plastic could be used in asphalt. But, he added, that research is still a few years behind rubber-modified asphalt.
