Experimental application of fully recycled asphalt concretes produced with chemical additives for patch pavement rehabilitation

The reuse of recycled materials, such as Reclaimed Asphalt Pavement (RAP), is one of the most widespread and sustainable alternatives to continuous exploitation of raw materials in the road pavements sector. Over the years, numerous studies have been conducted on the use of RAP in the production of Hot Mix Asphalt (HMAs) in different percentages and with several bituminous binders and additives. At the same time, little attention was paid to the possibility of using this recycled material as HMA for small road maintenance interventions. Cold Mix Asphalt (CMA) is still the material widely adopted for potholes repairs and patch pavement rehabilitations, despite its lower performance if compared to HMA. The idea developed in the present research is the possibility of using the hot recycling technology for the production of patch asphalt for potholes and utility cuts repairs. In particular, the focus of the study was the development of an HMA produced with 100% RAP and without the addition of bituminous binders. Thus, three different chemical additives were tested for the experimental recycled HMAs. Promising results have been obtained in the laboratory characterization, showing that the recycled materials can have physical and mechanical performances comparable to HMA produced with virgin aggregates and bitumen.