Perpetual pavement design for flexible pavements in the US

Long lasting asphalt pavements have been designed and constructed in the United States for many decades. Pavements that have avoided structural failure in the presence of heavy traffic and which require only periodic resurfacing are advantageous in terms of minimizing life cycle cost and user delays. Such pavements are known as perpetual pavements and the keys to their performance have become evident through a number of studies. These pavements have features that allow them to minimize critical responses to loading. Furthermore, recent studies have confirmed the likelihood of strain thresholds below which damage does not seem to accumulate in pavement structures. A design procedure (PerRoad 2.4) has been developed that encompasses these principles, and performs a Monte Carlo simulation for a probabilistic analysis of critical pavement responses. The designer can then select a pavement section that minimizes the risk of structural failure.