Use of Stabilized Steel Slag in Pavements

Road transportation is the most preferred mode of transportation as it effectively connects the populated and rural areas with ease. With 5.89 million kilometers of road, India boasts of having the 2nd largest road network in the world. About 15,000 tons of natural aggregates are required to construct one kilometer of flexible pavement, which leads to inadequacy of the most crucial construction element of the flexible pavement. This paper investigates the possible utilization of steel slag stabilized with fly ash in the base layer and subbase layer of flexible pavement using GGBS and lime as binder. Steel slag was replaced by 10, 20, 30, and 40% of fly ash by weight, and then different percentages of binder (GGBS and lime) in the range of 3–12% were added to the steel slag-fly ash mix. Compaction test and unconfined compressive strength test were carried out on different trial mixes and the optimum mixes for base layer in flexible pavement were decided as per the IRC SP 20 criteria. Durability test and cyclic triaxial test were also carried out on the optimum mix. Finite element analyses were performed for a flexible pavement system with five layers, and the service life of the pavement with the proposed mix as the base material was compared with that of the pavement with WMM base layer.