Effect of Recycled Aggregates and Polymer Modified Bitumen on the Marshall Properties of Hot Mix Asphalt- A Case Study

Abstract

The main objective of this study was to assess the performance and physical properties of hot mix asphalt mixes incorporating recycled aggregates from demolished concrete and compare them with an unmodified hot mix asphalt mixture. Using recycled aggregates offers potential environmental benefits by reducing the load on landfill sites associated with demolished concrete waste. Hot mix asphalt mixes were prepared using the Marshall mix-design technique, with varying proportions (0%, 25%, 50%, and 75%) of recycled aggregates replacing the coarse virgin aggregates. The resulting mixes were compared to a control sample. It was observed that with an increase in the proportion of recycled aggregates, the stability of the mixes decreased. Additionally, the number of air voids and voids filled by mineral aggregates increased. However, laboratory tests indicated that the recycled aggregates modified mixes exhibited comparable performance to conventional hot mix asphalt mixes while providing improved environmental advantages through the recovery and reuse of waste concrete aggregates. These findings highlight the potential of utilizing recycled aggregates in hot mix asphalt as a sustainable approach in asphalt pavement construction.