10.INTERNATIONAL GAP SUMMIT SCIENTIFIC RESEARCH CONGRESS
PERFORMANCE OF GRANULAR COLUMNS USED FOR SOIL IMPROVEMENT UNDER LATERAL LOADS: 3D-FDM
Granular columns have been widely used in soil improvement as an effective solution for increasing the bearing capacity of weak soils, reducing soil settlement, and controlling lateral soil movement. This paper aims to investigate the behavior of granular columns with and without geogrid encasement under lateral loads for reducing soil horizontal sliding. The research employs numerical analyses via finite difference method to evaluate the impact of various parameters including length-to-diameter ratio (L/D), elastic modulus of geogrid encasement on shear stress, and lateral deflection of columns in both homogeneous and non-homogeneous sand. The findings suggest that increasing the elastic modulus of geogrid increases shear stress in all L/D ratios, with maximum shear stress developed in end bearing columns for homogeneous sand and in the column of L/D=10. On the other hand, in the nonhomogeneous sand, it was found that maximum shear stress occurred as L/D is equal to 10. Furthermore, increasing the elastic modulus of geogrid decreases lateral deflection for all L/D ratios. The study identifies two different failure modes; shear failure in ordinary granular columns and bending failure in geogrid encased granular columns. Additionally, the results indicated a reduction in lateral deflection of geogrid encased granular columns in the shear plane as compared to ordinary granular columns. This finding highlights the effectiveness of geogrid encasement in improving the stability of granular columns under lateral loads.
