Implementation of a performance evaluation methodology for asphalt mixtures in Panama.

Abstract

Traditionally, asphalt mixes are based on volumetric designs. Despite its accessibility and widespread application, this methodology is not able to fully define the expected behaviour of in-service pavement. In this sense, Superpave design concepts consider the mechanical characterisation of the asphalt binder, traffic, and climate as complements to the volumetric parameters. This makes it an attractive alternative to increase the control and reliability of mix design. Based on these design principles, performance evaluation methods have been developed to determine the in-service capacity of the mix. However, in Panamá there is still no requirement to comply with these criteria, therefore, there is no test procedure or reference performance thresholds. This can lead to uncertainty and deterioration not considered in the design. For this reason, this study reviews methods developed to evaluate the performance of asphalt mixtures. In addition, the concepts of an evaluation process are implemented in a national project. The results indicate that it is possible to implement mechanistic concepts within the evaluation of local asphalt mixtures. In fact, the evaluations performed meet the thresholds suggested by the protocol. This means that the asphalt mix can perform satisfactorily during its service life. This evaluation approach represents a paradigm shift from traditional design. In fact, performance evaluation can lead to design optimisations that generate significant savings over the life cycle of the infrastructure.