Towards a practical screening test method to characterise reclaimed asphalt based on a cracking-based brittleness index

To maximise the use of reclaimed asphalt (RA), it is necessary to understand better its behaviour from a mechanical point-of-view. In this paper a new methodology is proposed based on which different RA materials are assessed in terms of their ageing state as reflected by cracking-related parameters. The proposed test method makes use of equipment commonly available in most asphalt laboratories, namely a gyratory compactor for the preparation of the test specimens and a compressive testing device. The results of this study demonstrate that the CTindex derived from IDT-testing shows very low values making it difficult to discriminate between the different ageing states. For this purpose, a new index is proposed able to track the brittle behaviour of RA, namely the cracking-based brittleness index (CBI). The CBI is a promising index which correlates well with DSR and FT-IR derived parameters.