NUMERICAL ANALYSIS OF CENTRALLY AND ECCENTRICALLY LOADED SQUARE FOOTING ON GEOGRID-REINFORCED SOIL

Abstract

Since Terzaghi gives his hypothesis “Theoretical soil Mechanics (1943)”, various researches have been published their works on the ultimate bearing capacity of the foundation. Most of these works are related to vertical centric loading. A few works have also done on eccentric loading. After going through a lot of existing literature, evidence suggested that reinforcement could be an effective method to increase the bearing capacity of foundation in eccentric and centric loading. But a detailed study for eccentric loading for square footing is not done. The purpose of this work is to find the optimum value of depth ratio (u/B), (h/B), width ratio (b/B), the number of geogrid layers (N), and also the effect of eccentricity on bearing capacity of the foundation. To achieve this numerical simulation of square footing (B=3m, D=0.5m) embedded in a reinforced sand bed is carried out using OPTUM G2 software. Mohr-Coulomb material model is used in the simulation. The impact of placement depth of geogrid layer, number of the geogrids, and width of geogrid layer on bearing capacity of footing for the various eccentric load (e/B = 0, 0.05, 0.1, 0.15) are examined. The Test result shows that the optimum value of u/B varies between 0.3–0.4, the optimum value of h/B varies between 0.3-0.4, the optimum value of b/B = 7, and the optimum value of N=3 for square footing.