THE BENEFITS OF ROAD-FRIENDLY SUSPENSIONS

Examined are the effects of 'road friendly' heavy goods vehicle suspensions on long term flexible pavement performance. The paper uses a deterministic Long Term Pavement Performance Model (LTPPM) to calculate pavement damage due to realistic traffic and environmental loading. The traffic is modelled first as a fleet of steel sprung heavy goods vehicles and second as a fleet of 'road friendly' air suspended vehicles. Two generic types of flexible pavement construction are considered representing a major road and a minor road. Pavement life predictions are compared for the two cases and with results from a simple road damage analysis based on the 'fourth power law'. The paper concludes that changing to a fleet of 'road friendly' vehicles would not significantly affect the life or maintenance costs of thicker asphalt pavements whereas the life of thinner pavements would be increased significantly if the vehicle fleet changed to road friendly suspensions.