Bearing Capacity of Strip Foundation on Soft Soil Reinforced with Stone Columns Using Method of Slices

Abstract

Stone columns are recognized as an environmently-friendly and cost-effective ground improvement technique. Stone columns are used in soft soil to increase the bearing capacity, reduce the settlement, increase the rate of settlement and reduce the liquefaction potential of the ground. This paper presents an analytical model utilizing the method of slices to predict the ultimate bearing capacity of the soil reinforced with a group of stone columns. The soil within the failure zone was divided into slices and the limit equilibrium technique was adopted to perform the analysis. Shear forces and passive earth pressure on the boundaries of each slice were determined. By utilizing a circular failure plane, the minimum inter-slice force coefficients were determined. The analysis was carried out using the Morgenstern-Price method to estimate the failure surface together with the bearing capacity of the reinforced ground. The failure surface was determined by trial and error to estimate the minimum factor of safety. The ultimate bearing capacity was defined by increasing the foundation load until the factor of safety of one was obtained. Results of the present theory were compared with those available in the literature, where a good agreement between the two was noted.