An overview on performance of steel slag in highway industry

Transportation and highway industry are going to use sustainable and recycling materials to address the two global issues: environment and energy. One of the materials is steel-furnace slag, a sustainable waste material, which includes two types, i.e. compound aggregate brings out as a consequence of Electric Arc Furnace (EAF) and Basic Oxygen Furnace (BOF). Steel slag can replace the traditional aggregates because it has a feature that almost same to those traditional aggregates and it is easily secure as a by-product from the steel industry. The recent experimental researches in preliminary studies have demonstrated chemical, mechanical and physical and properties of the steel slag. California bearing ratio (CBR) value of steel slag is between 200 and 300%, whereas CBR of crushed aggregate is only from 80 to 100%. Furthermore, asphalt mixture using steel slag presents better mechanical characteristics than those of the corresponding asphalt with 100% natural aggregate. Combination of 30% steel slag and 70% natural aggregates in bitumen mixture shows excellent performance as surface course of roads. Hence, operation of steel slag in road construction reduces land fill, saves natural resources and improves the strength of pavement to sustain a heavier and higher volume of vehicles. The overall purposes of this review paper are collecting chemical, physical and mechanical characteristics of steel slag for illustrating its performance, highlighting the previous studies on the use of steel slag in road construction and the effect of different percentage of steel slag upon pavement as a replacement for natural aggregates.