The effect of stone column geometry on soft soil bearing capacity

• Published in: International journal of geotechnical engineering 2022-02, Vol.16 (2), p.200-210
• Main Authors: Hamzh, Alarifi, Mohamad, Hisham, Bin Yusof, Mohd Fairus
• Format: Article
• Language: English
• Subjects: bearing capacity; non-uniform column; numerical analysis; PLAXIS-2D; Stone column
• ISSN: 1938-6362; 1939-7879
• DOI: 10.1080/19386362.2019.1666557

Stone columns are one of the common types of ground improvement methods that applied to reduce the settlement and increase the stability of structures. This paper focuses on the non-uniform diameters of the stone column and aimed at providing some practical insights into the design by reducing the constructing material of the stone column with increasing the bearing capacity of the soft soil. In this study, two dimensional (2D) Finite Element analyses through PLAXIS 2D were performed to investigate the bearing capacity of uniform and non-uniform stone columns in soft soil. A Mohr-Coulomb constitutive soil model was adopted in the numerical analyses. The non-uniform stone columns modelling by creating two different diameters and lengths. The upper diameter d 1 was always larger than the lower half diameter d 2 with investigated ratio d 2 : d 1 of 1:2, 1:4 and 1:5. The columns were 10 m long but varied in diameter length with nine different length ratios (l 1 : l 2 ). By comparing between uniform and non-uniform shapes, one can determine the optimum column's design. The highest bearing capacity obtained by the non-uniform stone column was one with the d 2 :d 1 ratio equals to 1:5. The most economical shape for the stone column (the least volumes used to construct stone columns) was achieved at a ratio of d 2 :d 1 = 1:2 and a length ratio of l 1 :l 2 = 3:7.