The Effect of Rigidity of Reinforced Stone Columns on Bearing Capacity of Strip Footings on the Stabilized Slopes

Abstract

The effect of slope-stabilizing stone columns on the bearing capacity of a rigid strip footing placed on a sand slope has experimentally and numerically investigated in this paper. A broad series of conditions has been tested by varying parameters such as the rigidity of stone columns and their spacing in a row. Different types of stone columns were studied including ordinary stone columns, encased stone columns, and concrete piles. Soil displacement fields were obtained via particle image velocimetry method. The results were analyzed to find qualitative and quantitative relationships among bearing capacity and various parameters. A series of finite-element analyses was additionally carried out on a prototype slope and the findings were compared with the results from the laboratory model tests. They were also used to complement the results of the model tests. The agreement between observed and computed results is found to be reasonably good in terms of load–settlement behavior and optimum parameters. Findings of the study showed that increasing rigidity and decreasing the stone columns spaces result in increasing bearing capacity of footing. This enhancement in bearing capacity is attributed to arching effect of soil between stone columns. The rigidity and spacing of stone columns had a significant effect on soil arching. Moreover, the load–settlement behavior of rigid footing is improved.