Abstract
Optimum design and maintenance of pavements require an accurate prediction of their deterioration process. This process is highly influenced by the uncertainties in traffic load and load distribution, and the parameter and model uncertainties associated with all mechanical properties of materials and structural behavior. This paper presents a model for optimizing the design of flexible asphalt pavement structures. The model takes into account the fatigue damage caused on the asphalt surface and the degradation of granular materials caused by repetitive loading cycles. Mechanical considerations are combined with construction and rehabilitation costs as well as financial factors such as the discount rate. Results of an illustrative example showed that the reliability based design optimization (RBDO) combined with a long-term maintenance policy of pavements produces appropriate integral designs. The analyses of the results have shown the advantages of the procedure proposed.