Suitability of Using Waste Polystyrene and Granite Dust Blend in Bituminous mixes in flexible Pavement Construction

This investigation focuses on enhancing the performance of asphalt concrete mixes for road construction through the incorporation of granite dust (GD) and waste polystyrene (WPS) as modifiers. This research paper seeks to utilize (GD) and (WPS) as filler in asphaltic mixture by adopting the dry process to evaluate the effect of (GD) and (WPS) mix interaction on asphaltic concrete physical properties. Laboratory investigation using varying percentage quantities (between 0% to 10%) of GD-WPS modified asphalt mixture. The mixtures were subjected to Marshall Stability Tests where the stability, flow, percentage air void, density and void in mineral aggregate were determined. The results obtained shows an increase in stability and density at 4% GD,- 2% PS mix for the different blends and then a gradual decrease as the Percentage of WPS increases. While flow and VMA (MDD) decreases at 4% GD,- 2% PS mix for the different blends and then gradually increases as the Percentage of WPS increases. The 4% GD - 2% PS Mix of the different blend investigated gave the optimal stability, flow, air void, density and VMA results and these values fall well within the recommended range for asphalt mixtures designed for heavy traffic conditions.