Comparative Study on Bearing Performance between Y-Section Pile and Conventional Pile

Y-shaped vibro-pile (referred to as Y-Section pile) is a newly developed pile based on traditional circular driven cast-in-place pile and the principle of peripheral expansion of various shapes with constant cross-section. Three-dimensional numerical model is built for Y-Section pile, circular pile, square pile and triangular pile with the same sectional area using finite element software ABAQUS. The pile material is elastic model as well as soil around pile and under pile is Mohr-Coulomb model. With the same cross-sectional area and under the same load, the settlement of Y-Section pile is the smallest, followed by triangular pile, square pile and circular pile in sequence; the average stress of pile-end soil of square pile is the greatest, followed by triangular pile, circular pile and Y-Section pile; the ultimate bearing capacity of Y-Section pile is the largest, followed by triangular pile, square pile and circular pile. Assuming that the lateral friction is of linear growth along pile shaft and of triangular distribution, the maximum lateral friction intensity at pile tip is different for various piles with the same cross-sectional area, and the largest is circular pile, followed by square pile, Y-Section pile and triangular pile. The maximum lateral friction intensity of Y-Section pile is up to 88.71% of circular pile and there is friction resistance weakening with various shapes.