Investigation of the behaviour of geosynthetic-reinforced stone columns

The paper represents a series of numerical studies relating to the performance of geosynthetic-reinforced stone columns in sand soil. To determine the behaviour of the encased column, parameters such as stone column diameter, modulus of elasticity of the stone, stiffness of the geosynthetic encasement and the load ratio were considered in non-linear static analyses resulted from applying gravity loads. The results are discussed in the form of axial load–settlement curves of the stone column, lateral deformation of a stone column, column bulging, stress concentration around the column and the load ratio of models. The results of numerical studies demonstrate that increased encasement stiffness gives rise to an increase in confinement pressure and load-bearing capacity. On the other hand, a decrease in the modulus of elasticity of the stone causes an increase in both soil horizontal stress and total stresses. Additionally, the stress concentration ratio value for encased columns with smaller diameters is more significant than that for columns with larger diameters, which is due to the mobilisation of confinement stresses in stone columns with smaller diameters.