Stabilization of Contaminated Soil in a Landfill Site with Ground Granulated Blast Furnace Slag

Abstract

The aim of the present work is to examine the efficacy of ground granulated blast furnace slag (GGBFS) as an additive to improve the engineering properties of contaminated soft soil. The soil is contaminated with heavy metals such as zinc, lead and copper. In this study, emphasis was given on engineering property improvement of the stabilized soil. Various soil physical parameters were determined as per guidelines depicted in BIS 2720. The dry density, unconfined compressive strength (UCS) and specific gravity (G) values of the soil increased substantially with the increasing amount (5, 10 and 15%) of GGBFS addition in the contaminated soil. The specific gravity and UCS values of collected soil were improved from 2.31 to 2.65 and 95 to 1877 kN/m2, respectively, when 15% of GGBFS was added to the untreated soil. The maximum dry density (MDD) of the untreated soil was improved from 1.32 to 1.90 g/cc for 15% addition of GGBFS. The concentrations of Zn, Pb and Cu in the contaminated soil were decreased by 70, 80 and 77%, respectively, after blending with GGBFS of 15% at a curing time of 28 days. The decrease in metal leachability and increase of strength properties of the contaminated soil clearly show that GGBFS material has a potential to be used as an additive for contaminated land stabilization and reclamation.