Life-cycle cost analysis system for pavement management at project level: sensitivity analysis to the discount rate

The Portuguese manual of pavement structures, despite the fact it uses a design period of 20 years for flexible pavements, states the importance of making a life-cycle cost analysis (LCCA) for a period of no less than 40 years. This paper presents a sensitivity analysis to the discount rate that was carried out on the application of a new LCCA system, called OPTIPAV, developed and programmed to help pavement designers to choose the best pavement structure for a road or highway. The OPTIPAV system uses the serviceability concept adopted by the American Association of State Highway and Transportation Officials (AASHTO) for use in the design of flexible pavements. The results obtained by the application of the new LCCA system clearly indicate that, for any combination between traffic and pavement foundation, the optimum pavement structure always remains the same or decreases in terms of structural capacity with the increase of the discount rate value.