Effects of overloading commercial vehicles on vehicle damage factor for the National Highways in Bihar

Abstract Overloaded vehicles and traffic growth have a significant impact on the pavement’s performance and service life. As a result, pavement construction and rehabilitation costs have drastically increased. The paper presents the results of the research, including analysis of axle-wise commercial vehicles with 24 h axle-load survey data over a one-year period. The information was collected from two sections of National Highway Road using a weigh-in-motion machine. The fourth power rule is used to calculate the VDF value of over-loaded, legal-loaded, and actual-loaded vehicles by converting the all-vehicle load into a standard axle load. This paper presents the axle-wise impacts of overloaded vehicles on the calculated VDF value. The analysis has shown that when only over-loaded traffic is considered, the class-2 VDF value is higher than the other classes of vehicles, and the class-5 VDF value is higher when all types of collected traffic—legal-loaded and over-loaded traffic are considered. The study concluded that 20% overloaded weight of vehicles increases the VDF value by about 3–4 times. The study reveals that the actual loaded VDF value should be considered during the design of new pavement instead of the VDF value of over-loaded and legal-loaded vehicles. This result may assist the pavement designer in calculating the thickness of the pavement layer and the construction cost of the pavement.