Bearing behaviour of floating and end bearing encased stone columns with different encasement materials

This paper investigated the bearing behaviour of group geosynthetic encased stone columns (GESCs) under rigid static loading. Several laboratory model tests were performed on the floating and end-bearing GESCs with different types of encasement materials. The stress distribution of the composite foundation was measured by the buried soil pressure cell, and the soil displacement was analyzed by the PIV technique. The results show that GESCs can effectively improve the bearing capacity and stiffness of the foundation. With the same encasement material, the bearing capacity of the end-bearing GESCs is greater than that of the floating ones. With the increase of the encasement material stiffness, the stress concentration ratio and stress transfer ratio of GESCs increase. Under the same load, the soil displacement decreases with the increase of the stiffness of the encasement material. This study provides a reference for the application of GESCs in the weak-bearing stratum.