Bearing Capacity of Foundation and Soil Arching in Rigid Floating Piled Embankments: Numerical Study

Abstract

The definition of rigid floating piles in engineering applications remains ambiguous. This paper develops a numerical model of piled embankments and the modeling method is verified through engineering cases. Utilizing this model, the critical bearing capacity of the foundation for rigid floating piles is firstly determined to be approximately 150 kPa. Subsequent parametric studies show that soil arching in a rigid floating piled embankment begins to occur when the ratio of the embankment height to the clear pile spacing H/(s − a) ≥ 1.6. However, plastic failure does not occur in rigid floating piled embankments due to the weaker foundation, indicating that soil arching cannot fully develop. Finally, factors of the embankment fill properties are examined and it is shown that the large friction angle and high cohesion greatly enhance soil arching and reduce settlement in the embankment. The vertical stress above the subsoil decreased by 34.9% with an increase in the friction angle from 20° to 40°. Also shown is that the increase in the cohesion from 1 kPa to 7 kPa reduced the settlement on the top of and the base of embankment by approximately 72% and 58%, respectively. It has also been found that rigid floating piles rely on end resistance and skin friction to sustain the superimposed load.

Keywords

• rigid floating pile
• piled embankment
• bearing capacity of foundation
• soil arching
• numerical simulation