Numerical and Physical Modeling of Soft Soil Slope Stabilized with Stone Columns

Document Type: Regular Paper


1 Ph.D. candidate, Department of Civil Engineering, University of Hormozgan, Bandar Abbas

2 Assistant Professor, Department of Civil Engineering, University of Hormozgan, Bandar Abbas, Iran



There can be many reasons for engineers to place the footings near a slope such as leakage of suitable sites or architectural considerations. One of the approaches to increase the amount of bearing capacity, especially in soft soils, is adding stone columns to the soil. In this research, the behavior of a strip footing placed near a stone column reinforced clayey slope was investigated. For this purpose, some small-scale model tests were performed on a clayey slope reinforced with stone columns. The effects of the length of the stone column and the length of encasement on the footing were studied. Additionally, vertical encased stone columns in a group arrangement were investigated. Some numerical analyses were also performed using the Midas GTS NX finite element software, and the factor of safety was studied. Results show that the optimum length was equal to four times the diameter of stone columns. It was observed that by increasing the length of encasement, the bearing capacity of strip footing was also increased. The safety factor of slope showed an increase when stone columns were added to the slope, but the maximum influence on the factor of safety appeared when the stone column was in the upper middle of the slope.


Main Subjects

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