Efficacy of Iron Ore Tailings and Blast Furnace Slag for Improving the Strength of Laterite Soil
摘要
Laterite is one of the widely occurring soil types in eastern and western India. It is particularly found in abundance in and around the city of Bhubaneswar in Odisha. The state of Odisha is one of the major producers or iron ore and steel in India. Iron ore tailings (IOT) are the mining byproducts left after the commercial extraction of iron from the ore. Blast furnace slag (BFS) is a non-metallic product formed in a blast furnace during the reduction of iron ore in a blast furnace. This study was carried out to see potential application and efficacy of IOT and blast furnace slag as candidates for improving the strength of laterite soil. For this purpose, iron ore tailings were collected from Bolani iron ore mines in Odisha and blast furnace slag from the Rourkela Steel plant. Laterite soil sample was collected from Mahura region of Bhubaneswar city. Firstly, the index properties and engineering properties of laterite soil, blast furnace slag, and iron ore tailings were determined in the laboratory. The properties such as grain size, Atterberg limits, maximum dry unit weight, and optimum moisture content, permeability, pH and shear strength, and CBR values were determined. Based on the tests, it was found that both IOT and BFS had good mechanical strength. Later, IOT and BFS were added to laterite soil in different percentages by weight (0% to 20%) and the unconfined compressive strength (UCS) and CBR values of the mixes were determined. The tests revealed that both IOT and BFS improved the CBR and unconfined compressive strength of laterite soil at 10% and 15% concentrations, respectively. The study suggests a sustainable approach to handling of iron industry wastes in geotechnical application.