Undrained Vertical Bearing Capacity of Pile Located near Soft Clay Slope
Abstract
The bearing capacity of shallow foundations on slopes is commonly calculated from proposed design charts or using empirical equations. However, there is little information that attempted to analyze the behavior of piles near slopes. This paper presents the results of numerical studies carried out on behavior of pile located near soft clay slopes under undrained vertical loading conditions. A series of three-dimensional numerical models was performed for various pile geometry, different distances of the pile and slope angle. The obtained results show that, as the pile embedded length increases, full formations of wedge failure occurs and, therefore, a greater axial capacity of the pile is mobilized. In addition, by decreasing the distance of the pile from the slope crest the lateral movement of soils increases and the lack of soils on the slope side of the pile tend to reduce the bearing capacity. Furthermore, by increasing the slope angle, the pile lateral displacement increases and, therefore, the eccentricity of the axial load on the pile will produce more additional bending moments in the pile and thereby the axial capacity reduction increases. The results of the analysis are presented in chart form as reduction factors (RF) on horizontal ground ultimate loads.
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