Evaluation of the potential of sasobit polymer as an additive in bitumen and asphaltic concrete

Abstract

This paper evaluated the effects of sasobit polymer (Sasobit®) on the characteristics of asphaltic concrete with a view to investigating its suitability as an additive in asphaltic concrete. Sasobit®, bitumen and aggregates were procured from a Construction Company site office, along Shagamu-Ibadan expressway. Sasobit® modified bitumen was prepared by adding Sasobit® to bitumen with increasing weight of Sasobit® at 1.0, 1.5, 2.0, 2.5 and 3 % by the weight of the bitumen. Penetration and softening point tests were carried out on the samples and the mix-ratio for the bitumen – polymer mixture was determined. Asphaltic concrete samples with and without Sasobit® were prepared. The samples were subjected to Marshall Stability test. The stability, flow, specific density, voids filled with bitumen (VFB), air voids (VA) and voids in the mineral aggregate (VMA) were
determined. The values of stability, flow, specific density, voids filled with bitumen, air voids and voids filled in the mineral aggregates for sample without Sasobit® were 13.63 kN 2.91 mm, 2.51, 64.64 %, 4.29 % and 18.19 %, respectively, while for those with Sasobit® at mix – ratio of 1.7 % bitumen – polymer mixture, the values were 14.67 kN, 2.41 mm, 2.55, 73.30 %, 3.96 % and 16.39 % respectively. The result showed that, Sasobit® as additive in asphaltic concrete improved its properties.

Keywords: Sasobit®, Asphaltic Concrete, Stability, Flow, Voids filled with bitumen, Air voids, Voids in mineral aggregate