THE RESISTANCE TO FATIGUE OF DRY ASPHALT RUBBER CONCRETE FOR SUB-BALLAST LAYER

The more and more frequent use of recycled materials within the road and railway infrastructures is now an irreversible trend. In this area the use of Dry Asphalt Rubber Concrete (DARC) in sub-ballast layer seems to be a suitable technique to reach high mechanical and environmental performance even if such material should be analyzed over a long time horizon. This paper presents the results of experimental research focused on the resistance to fatigue of Dry Asphalt Rubber Concrete in sub-ballast layers; the survey has been carried out using four-point bending test (4pbt) on mixture samples with different rubber contents. The results of fatigue in DARC have been compared with the performance of different mixes such as a standard hot mix asphalt without rubber and a rubber-modified asphalt concrete (RUMAC-Dry). It has been found that fatigue performance of Dry Asphalt Rubber Concrete is broadly comparable to other mixes, making it a very attractive material in terms of technical and economic skills.