Impact of Overweight Traffic on Pavement Life Using Weigh-In-Motion Data and Mechanistic-Empirical Pavement Analysis

The objective of this study is to evaluate the impact of overweight traffic on pavement life using mechanistic-empirical analysis approach. The state-of-practice mechanistic-empirical pavement design and analysis software (Pavement-ME) was used to predict pavement life under different traffic loading scenarios. Field performance data at the sites where the WIM data were collected were analyzed to estimate the pavement service life at field condition. The pavement structures considered in the analysis include flexible pavement and composite pavement with different combinations of layer thickness. Different distribution patterns were observed between the overweight and non-overweight traffic in terms of truck classes and axle load spectra. The reduction ratio of pavement life was used to normalize the effect of overweight truck at different conditions. A linear relationship was found between the overweight percentage and the reduction ratio of pavement life regardless of the variation in traffic loading and pavement structure. In general, it shows that 1% increase of overweight truck may cause 1.8% reduction of pavement life. Through the comparison between the pavement life predicted from the M-E analysis and estimated from field performance data, M-E analysis was proved to be a valid approach to quantify the impact of overweight truck on pavement damage in the network level.