In response to another round of attacks on asphalt pavement by the PCA and NRMCA, NAPA has released a special report critiquing a report from the Concrete Sustainability Hub (CSH) at MIT.
The NAPA Special Report was written by NAPA Dr. Howard Marks & Dr. Richard Willis at NCAA T. The CSH report concludes that vehicles consume less fuel when they travel on stiff concrete roads. This is a conclusion that has ONLY been reached in concrete industry research and has NEVER been reached in a study performed by an independent institution.
To the contrary, literature reviews have shown that (1) large-scale roughness is the most important parameter affecting rolling resistance and (2) the stiffness of a road does not have a significant impact on rolling resistance or fuel economy. In many states, asphalt pavements are constructed to more exacting smoothness specifications than concrete pavements, so they are smoother to begin with, said Mike Kvach, Executive Director of the Asphalt Pavement Alliance. Concrete pavements have joints, that is why you hear ka-thunk, ka-thunk when driving on concrete and they just get rougher over time. Smoother pavements mean better fuel economy, less wear and tear to motor vehicles, quiet andd comfort for drivers and passengers, and longer-performing pavements.