Determination of shear strength properties of coarse‐grained materials for stone column

Abstract

AbstractThe stone columns created using a vibro – replacement technique are often used technology of ground improvement. Suitable geological conditions for stone columns include loose coarse – grained soils and soft to firm fine – grained soils. The stone columns cause increasing of strength and deformation properties of the original subsoil. The design of stone columns must be based on properly determined properties of original subsoil as well as properties of the material of stone columns. The article presents and analysis results of direct shear tests of three different types of coarse – grained materials which are used for stone columns. The shear strength of coarse – grained material was determined using large – dimensional direct shear apparatus, which is required for this type of soil. Shear tests were executed for different values of the unit weight. High values of peak and residual angle of shear strength were determined for all three tested materials also in the loosest state. The initial shear strength was measured in the case of coarse – grained material consisting of the quarry stone.