Utilisation of steel slag as a granular column to enhance the lateral load capacity of soil

Granular columns are widely used to enhance the bearing capacity of weak soil. The filling material of columns is generally stone, gravel or sand. The use of industrial wastes such as steel slag in civil engineering applications not only reduces environmental pollution, but also leads to cost benefits. So far, many studies have been done on the behaviour of granular columns with and without geosynthetic encasement under vertical loads; however, very limited studies were conducted on the behaviour of waste granular columns with and without geosynthetic encasement under lateral loads. Therefore, this study aims to evaluate the lateral load capacity of steel slag granular columns reinforced with geosynthetic using a large direct shear test apparatus. Results demonstrated that the use of steel slag column improved the lateral load capacity of soil. The use of geosynthetic encasement in floating steel slag column could significantly enhance both the peak and critical state shear strength. The results indicated the viability of using steel slag column as a soil reinforcement providing sustainable and technical benefits mainly when using geosynthetic reinforcement.