Deformation behaviour of ground improved by reinforced stone columns

Stone columns are extensively used for ground improvement for supporting various flexible and rigid structures. However, in very soft soil they encounter excessive settlement due to inadequate lateral confinement by surrounding soil. Reinforcing the stone column with geosynthetic enhances the performance of stone columns. The reinforcement makes the column stronger and stiffer. Also lateral squeezing of stone aggregate into surrounding soft soil is prevented and vice-versa. This paper investigates the load settlement behaviour of ordinary and reinforced stone column through laboratory model tests. Tests were performed with different geosynthetic modules for the reinforcement of stone column. The results from the load tests indicated a clear improvement in load capacity of the stone column due to reinforcement. The increase in the axial load capacity depends very much upon the modulus of the reinforcement and diameter of the stone column. FEM analysis was carried out to understand the behaviour of reinforced column. The findings of experiments are in conformity with FEM analysis.