Researchers work 'tirelessly' to find answers

Researchers at the Illinois Center for Transportation are devoting considerable time and effort on a tool to help state agencies and highway construction materials engineers evaluate the effects of new-generation wide-base tires on existing pavements and to provide guidance about the use of wide-base tires on pavements.

Wide-base tires offer important economic, safety, and environmental benefits. They improve fuel economy by reducing weight and aerodynamic drag, and they have the potential to reduce noise and improve stability. However, the impact of wide-base tires on pavement life must also be considered.

Toward that end, the research team is developing theoretical models that will be validated by tests of wide-base tires on heavily sensored, full-scale pavements comprising various materials and layer thicknesses in different climatic regions of the United States. The tool will be used to compare conventional dual-tire assemblies (used on 18-wheel trucks) with new-generation wide-base tires, without the need for actual testing—hence, “tire-less.”

The model uses nonuniform tire stresses, actual loading, and contact areas to provide a more accurate understanding of pavement damage and predict its performance over time. The model will be validated with measurements of pavement performance captured in highly instrumented field sections as well as full-scale pavement sections exposed to accelerated vehicular loading testing.

The combination of model results and actual pavement responses will be used to train an artificial neural network, resulting in a powerhouse analysis tool. The tool will allow engineers to assess the impact of different tire types and configurations on pavements, ultimately providing a way to evaluate various scenarios not previously considered.

According to Eric Weaver, Research Civil Engineer for the FHWA Office of Infrastructure Research and Development, this project capitalizes on an extensive pool of resources beyond the pooled-fund state highway agency participants. It also benefits from other relevant research projects both past and present, federal and nonfederal.

“This collaboration is important to achieve the most robust product at the least amount of cost for all involved. It is also important to the goal of increasing cooperation and exposure while reducing duplication of effort,” said Weaver.

The project is sponsored by FHWA; state departments of transportation in Illinois, Minnesota, Montana, New York, Oklahoma, Texas, and Virginia; and the tire industry. Research partners are the University of California at Davis, Texas A&M University, the Florida Department of Transportation, Delft University of Technology in the Netherlands, and the Council for Scientific and Industrial Research in South Africa. The Ohio Department of Transportation and Ohio University are also collaborators in this research.