Teresa Madaleno

The transportation sector is always looking for ways to save fuel. Many people know that even little steps like not idling and making sure tires are properly inflated can make a difference when it comes to a vehicle’s fuel efficiency. Now some engineers suggest that properly maintained roadways can also improve fuel economy.

A recent study by MIT’s Concrete Sustainability Hub (CSHub) and the California Department of Transportation demonstrated that pavement vehicle interaction, such as roughness and deflection, accounts for one percent of fuel consumption on highways. While the research team doesn’t believe that passenger cars would achieve the same results, they do see how road stiffness could make a big difference when talking about 40-ton trucks, with up to 4 percent gas mileage savings.

As reported by the Massachusetts Institute of Technology, CSHub provided the California Department of Transportation with a great deal of data from ground-penetrating radar. This data outlined the road’s structure, as well as providing GPS information on every crack, rut and bump in California’s 50,000 lane-mile road system. Using a small-scale approach, where a rigid steel tire rolls along a polymer pavement, they measured the horizontal force required to move the tire forward at different speeds with different loads. This allowed them to examine the interaction between the wheel and pavement.

The researchers worked through between 40,000 to 50,000 calculations for each mile in the network and then made rankings to determine the fastest path reduction of fuel consumption. Through this model, excess fuel consumption can be calculated. It’s a model that can allow engineers to choose paving projects that will have the biggest impact on fuel savings, which of course leads to lower greenhouse gas emissions.

The testing did involve tests of pavement life cycle, but more investigation is needed in this area.

The team involved in the joint CSHUB and Caltran study are now saying that decision makers, such as engineers and politicians should think of infrastructure as part of the solution when dealing with the environment.