Impact of Payload Spectra of Heavy Vehicles on Pavement Based on Weigh-in-Motion Data

Truck traffic is a crucial factor that results in pavement damage. The increasing demand of freight transport contributes to rising truck volumes. In some countries there is a trend toward using larger vehicles, and road authorities are concerned about their effect on pavement because of the lack of pavement maintenance funding. This paper investigates the efficiency of freight transport by comparing the effect of six-axle articulated trucks (semi-trailers) and nine-axle articulated trucks (B-doubles) with regard to pavement performance when carrying various payloads based on weigh-in-motion data. Mathematical models were developed to help decision makers consider how to distribute road freight, to minimize pavement damage induced by the different types of trucks. It was found that there is reduced pavement damage when one or more of the following conditions are met: The payload of the trucks gets closer to their optimum value, the percentage of the empty vehicles is decreased, and more freight is undertaken by B-doubles. In addition, a simplified pavement performance prediction model was used as a basis to determine the future pavement maintenance and rehabilitation (M&R) schedules, and therefore help in comparing the long-term pavement treatment costs for different traffic loading scenarios. The outcome from the economic analysis shows that there would be significant benefits in the pavement M&R costs over the pavement service life by improving the distribution of freight.