Parametric Study of Factors Affecting Flexible-Pavement Performance

A new whole–life pavement–performance model (WLPPM) that is capable of making deterministic pavement–damage predictions due to realistic traffic and environmental loading has been developed. A vehicle simulation is used to generate dynamic tire forces that are a function of distance along the pavement. These dynamic tire forces are then combined with the appropriate pavement primary–response influence functions to give primary–response histories at regularly spaced points along the pavement. The primary–response histories are then transformed into an increment of damage at each point along the pavement due to a single vehicle pass, and the surface–roughness profile is updated. This procedure is then repeated until pavement failure occurs. Using the WLPPM, the performance of two classes of pavement are examined operating under climatic conditions typical of the United Kingdom. It is concluded that both dynamic vehicle loads and asphalt–layer stiffness variations can significantly influence long–term flexible–pavement performance.