Akhila K M, Anusha T M, Jagadeesh H S
Abstract: Stone Mastic Asphalt (SMA) is a rut resistant layer that counteracts the permanent deformation. Currently SMA mix is relatively costly for paving roads because it requires more durable aggregates, higher asphalt content and typically a modified asphalt binders or fibers. In order to reduce the initial cost of SMA mix other suitable alternative materials or industrial waste such as steel slag, bag house dust, Reclaimed Asphalt Pavement (RAP), Construction and Demolition (C&D) waste, Ferro-Chrome Slag (FCS) and baghouse dust etc. can be used. RAP is found to be effective for SMA mix. RAP reduces the whole cost of the project by replacing the aggregates, and bitumen. The main objective of this study is to evaluate the SMA mixes which utilize RAP with and without an elastomer modifier. The methodology used in this research is material testing, marshall mix design and performance studies including tensile strength ratio, rutting, and fatigue test. It was observed that without modifier 50 % of RAP and with modifier 80 % of RAP can be used in the SMA mix. The use of an elastomer modifier can enhance the engineering properties of the mix when compared to the conventional SMA mix.
Keywords: Stone matrix asphalt, Reclaimed asphalt pavement, Marshall properties, Tensile strength ratio, Rutting, Fatigue life