The Massachusetts Institute of Technology (MIT) has released the first in a series of reports from a two-year life-cycle performance study of both concrete and asphalt pavements by the Concrete Sustainability Hub, its research team. The final report is expected to be released Aug. 31, 2011.

The goal is to benchmark how the nation's roads are performing and to build a model to quantify the carbon emissions associated with pavement material selection over a 50-year lifetime.

Researchers are analyzing three roads in California to determine how those pavements operate under varying levels of traffic. “One issue is understanding how fuel consumption varies on different pavements, with emphasis on what a degraded infrastructure means for fuel consumption,” says co-director John Ochsendorf, an associate professor for MIT's departments of architecture and civil and environmental engineering.

During the first year of the analysis, researchers discovered that:

  • For high-volume roads, the use phase of the life-cycle can account for up to 85% of carbon emissions.
  • There's potential for significant fuel-efficiency savings for vehicles on concrete pavements over asphalt, which could lead to substantially lower life-cycle carbon dioxide (CO2) emissions.
  • Varying scheduled maintenance work and lane closures can reduce CO2 emissions for concrete pavements over the life of the road.