Mechanical characterisation of reclaimed asphalt mixes for modelling purposes

Reclaimed Asphalt (RA) is a 100% recyclable material, but at present in Europe the re-use of RA in mixes is limited and a huge amount of it is simply wasted. Furthermore, the recycling of asphalt often involves a certain downgrading of the material. Therefore, it is desirable to define technologies that will allow the use of more recycled asphalt in exposed layers of the road structure. Of course, the mechanical properties of reclaimed asphalt vary a great deal and at present it is difficult to use the material in an optimum manner. The proposed laboratory research is born from this necessity and has the aim of evaluating the mechanical properties of the mixes, with and without RA. The results will be analysed and discussed to understand the change in mechanical properties due to the addition of high percentages of RA and to extrapolate input parameters for the calibration of a model that will be able to predict performance and end of life of RA mixes. The present paper will focus only on the explanation of the experimental programme chosen to characterise the materials and on the discussion of the results; more details about the modelling part are explained and discussed in other papers. This study was performed as part of research that is currently being conducted in the framework of the FP7 European Project 'Re-Road'.