A review on utilization of steel slag in hot mix asphalt

Road construction involves large quantity of construction materials, primarily obtained from natural sources. Utilization of waste materials in construction activities can reduce burden on these natural sources. To achieve sustainable development, use of steel slag as a substitute to natural-aggregates has gained significant attention. Steel slag as aggregate has many well-known applications in road construction such as, hot mix asphalt, cement concrete mix, antiskid-layer, granular-base and subbase layers. This paper review development in various aspects of utilizing steel slag aggregate in dense graded hot mix asphalt. Properties of steel slag can significantly influence performance of roads. Chemical composition and physical and mechanical properties of steel slag have been reviewed in consideration of its suitability in asphalt mix. Findings from asphalt mix design studies indicate that, steel slag asphalt mix can be designed to satisfy both volumetric and mechanical properties. However, caution need to be exercised to ensure that addition of steel slag does not lead to undesirable change in performance of mix. Review of laboratory and field performance evaluation studies related to skid, moisture, fatigue and rutting failures are presented in the paper.