Study on Uplift Capacity of Belled Pile in Sandy Soil

This paper presents a practical evaluation method for determining the uplift capacity and the relationship between uplift resistance and displacement of belled piles in sandy soil. Field tension tests were conducted with varying bell angles, and the results revealed that the uplift resistance varies with the bell angle. The relationship between the uplift capacity factor and the bell angle was found to be expressed by an exponential function. Furthermore, it was observed that the relationship between normalized uplift resistance and normalized displacement can be approximated by a hyperbolic function for small bell angles and by an exponential function for larger bell angles.