Evaluation of recycled glass and steel slag as partial replacement of filler in hot mix asphalt

Abstract

Recent studies have revealed the need to increase the volumetric properties of hot mixed asphalt (HMA) with various industrial solid waste materials. Hence, this study was carried out to investigate the use of crushed glass (CG) and steel slag dust (SSD) as fillers partially replaced in HMA. The optimum bitumen content (OBC) suitable for design mix was determined. The tested samples were prepared with CG and SSD separately, and the combination of the best results in each were mixed equally (CG+SSD) to replace filler partially with 5, 10, 15 and 20% respectively. Both conventional HMA, and modified samples were examined to determine their volumetric properties and stability. The OBC suitable for HMA mix design was 6%. The addition of CG, SSD, and CG+SSD had significant improvement on the properties of HMA, and the best results was observed at 15% replacement with 3.28%, 7.81%, and 55.49% increase in stability respectively compared with control HMA. The ANOVA results on the modified asphalt revealed that void in mix was not influenced by the modification of CG and SSD. In conclusion, 15% of CG+SSD as filler partial replaced in HMA can be considered reasonable alternative filler for concrete asphalt mixture production.