The massive use of fuel required by road transportation is accountable for the exploitation of non-renewable energy sources, is a major source of pollutants emission, and implies high economic costs. Rolling resistance is a factor affecting vehicles energy consumption; the structural rolling resistance (SRR) is the component of rolling resistance that occurs due to the deformation of the pavement structure. The present research presents an investigation on the SRR in order to identify its causes, characterize it and develop the instruments to predict its impact on fuel consumption for different road and traffic conditions.First the methods to calculate the SRR on asphalt and concrete pavements were developed. The structural rolling resistance is calculated as the resistance to motion caused by the uphill slope seen by the tires due to the pavement deformation. The SRR can be converted into fuel consumption using the calorific value of the fuel and the engine efficiency, and the greenhouse gas emissions associated with it can be calculated.Purely mechanistic models were used to determine the structural rolling resistance, and the fuel consumption associated with it, on 17 California pavement sections under different loading and environmental conditions. The results were used to develop simple and rapid-to-use mechanistic empirical heuristic models to predict the energy dissipation associated with the structural rolling resistance on any asphalt or concrete pavement.The difference in terms of fuel consumption and pollutants emissions between different pavement structures can be significant and could be included in economic evaluations and life cycle assessment studies. For this purpose, a practical tool was createddeveloped, based on the heuristic models, that allows the calculation of the fuel consumption associated with the SRR for any given traffic and pavement section. Examples of applications of such a tool are presented and discussed.
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