BEHAVIOR ANALYSIS OF PILES IN LAYERED CLAYS UNDER ECCENTRIC AND INCLINED LOADS BY IMPROVED FINITE POLE ELEMENT METHOD

The behavior of piles in layered clays under eccentric and inclined loads can not be analyzed by traditional finite pole element method if P-Δ effect is significant. To treat this problem, this paper develops the improved pole-element stiffness equation accounting for P-Δ effect, and proposes improved finite pole element method. The horizontal displacement of pile is assumed to be in the form of longitudinally cubic power function. The moment/horizontal-displacement relationship and shear/horizontal-displacement relationship are determined according to the mechanical deferential equation of piles under eccentric and inclined loads. Detail procedures to calculate displacements and internal forces of piles are presented. The accuracy of the method is demonstrated through its application in a real project. Furtherly, effects of depth, pile material, pile length above ground, pile inclination, eccentricity and inclination of loads are investigated.