Numerical study of the bearing capacity of the foundation adjacent to the clay slope reinforced with a stone column

Document Type : Research Paper


1 Assistant Professor, Department of Civil Engineering, Faculty of Engineering, Hormozgan University, Bandar Abas, I. R. Iran.

2 MSc Student, Uinversity of Hormozgan


Soft and loose soils have always been the focus of attention due to their high settlement and insufficient bearing capacity. The foundations on soft soils and soil slopes containing this type of soil should be modified for high probability of failure. There are various ways to improve these soils, which vary greatly depending on the environmental conditions, site priority, the degree of softness, cost of materials used. Stone column is one of soft soil modification and soil slopes safety factor improvement methods which is economical and easy to implement. The aim of this study is to conduct a numerical study to investigate the effect of stone columns on the bearing capacity of the clay slope and its stability using the FLAC3D finite difference software. the slope is modeled in three dimensions with appropriate dimensions and boundary conditions. The bearing capacity was obtained by stress control procedure and slope safety factor was calculated by shear strength reduction method. In general, two types of failures observed in stone columns. The columns were Located under the footing Were exposed to phenomenon of bulging and the columns were Located outside the footing Were exposed to phenomenon of lateral displacement. The results showed that in general, the stone column will improve the stability of clay slope and its bearing capacity. The use of stone column below the foundation will affect the most on increasing bearing capacity and the effect will decrease by increasing center to the center distance of foundation and columns, so that at 4 times the diameter of stone column it will not have much effect on the bearing capacity. In the case of group columns, the arrangements are along the length of footing is preferred over the arrangements are along slope due to the higher replacement area.


Main Subjects

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