Portuguese Experience on Asphalt Pavements Design Supported by In Situ Performance Evaluations

The use of most suitable material models for the structural behavior modelling in the pavement design process is essential to find the most technical and economical solutions, taking into account the real pavement conditions, such as traffic and weather conditions. For this purpose, laboratory tests and the performance evaluation of experimental pavements during in situ tests have a special importance. This paper presents the results ofresearch based on the instrumentation and testing of some experimental pavement sections. At the same time, an extensive laboratory program was also undertaken to obtain the geometric, physical and mechanical properties of pavement materials. Bituminous mixtures were tested in indirect tensile tests. Granular materials were submitted to repeated load triaxial tests and an elastic nonlinear model was verified and calibrated to describe the resilient behavior of the pavement materials. This model was incorporated in the finite element program used in the modeling of the structural behavior of experimental pavements during the load tests. The comparison between results from field monitoring and from numerical modeling confirmed the importance of in situ performance evaluation to achieve a better understanding of the materials behavior useful for a technical and economical pavement design.