Återvinning av asfalt, En kartläggning av användning av returasfalt vid tillverkning av nya asfaltbeläggningar

Sammanfattning: To achieve a society with sustainable development, the use of valuable non-renewable resources, i.e., the crude oil used for bituminous binder and aggregates must be changed. Meanwhile, the road network is expanding worldwide, requiring more recourses. The asphalt concrete can be recycled up to 100% after being removed from an existing road pavement, which ensures the sustainability of the asphalt pavement construction process. The reclaimed asphalt pavement (RAP) handling in the process of mix design is critical, especially the mixing and compaction temperatures for high RAP mixes. In this report, the production challenges and common pavement distresses of RAP content mixtures are identified and methods to improve the mix design as well as production technology in order to allow manufacturing of sustainable mixtures are described. The climatic, environmental and economic aspects of different processes are also discussed to examine if the use of RAP is profitable. This was done through a comprehensive literature study. The aim of this master thesis report is to summarize the state-of-the-art of use of RAP aggregates in new asphalt mixtures. Several studies have revealed positive responses of the recycled asphalt mixtures, provided that RAP is properly managed, with high content of RAP. The results from this literature study show that the amount of RAP in asphalt mixtures can be increased by applying good management practices of the RAP.