Truck Design and Usage Related to Highway Pavement Performance

The function of a pavement is to serve traffic safely, comfortably, and efficiently at reasonable costs. Automobile traffic typically accounts for the major volume of traffic using high-type facilities. However, heavy truck traffic accounts for the major portion of accumulated fatigue and therefore requires greater structural designs. Truck design and usage has tended toward larger vehicles and greater payloads. The impact of elements of truck design and usage (such as suspension systems, floating axles, axle configurations, uniformity of loading, payloads, etc.) on fatigue damage are illustrated. The effects of increasing vehicle loadings and increased tire pressures are related to potential for rutting of asphaltic concrete pavements. Mechanisms for implementation of vehicle damage factors and accumulated pavement fatigue in the assessment and allocation of costs to highway users also are presented