Bearing Capacity of Stone Column-Reinforced Soil Under Eccentric Load

This paper focuses on a numerical study for estimating the undrained bearing capacity of stone column reinforced soil subjected to eccentric loads. Three-dimensional (3D) finite element analysis is performed on a group of four end-bearing stone columns with a rigid square footing on the ground surface. The soft soil and the stone column adopted the Mohr–Coulomb (MC) constitutive soil model with a non-associated flow rule. Various area replacement ratios and eccentricity values are applied to demonstrate the effects of one-way eccentricity and two-way eccentricity on the undrained bearing capacity of the non-reinforced soils and reinforced soils. The area replacement ratio varies from 0.2 to 0.5, and the eccentricity values range from 0.25 to 1.5 m. The results show that the bearing capacity of non-reinforced soils and stone columns reinforced soils decreases as the eccentricity increases. The bearing capacity for both cases due to eccentric loads can be estimated by implementing the conventional effective area method with the proposed modified equations of effective width for one-way and two-way eccentricity, respectively. The shear failure mechanism changed from symmetry to one-sided as the eccentricity increased. The extensive bulging failure is observed at stone columns near to the load, while bending is discovered for columns on the opposite side.