竖向荷载作用下斜桩承载特性数值分析

Numerical analysis of bearing characteristics of inclined piles under vertical load

近年来,斜桩在桥梁、码头、海上钻井平台及大型输电线路塔架基础等工程中得到广泛应用,研究不同倾角斜桩的荷载传递及承载特性实用意义较大。基于ABAQUS软件,考虑桩土接触特性,模拟分析了不同倾角斜桩的承载特性。结果表明:桩身倾角不大于10°时,倾斜角对单桩的极限承载力影响不大,但会在桩身产生一定弯矩以及桩顶产生一定的水平位移;桩身轴力沿桩长方向的衰减速率随桩身倾角的增大而增大;斜桩桩身弯矩主要分布在桩顶下1/2桩长范围内,其最大值的位置不受桩身倾角以及桩顶竖向荷载的影响;斜桩桩身侧摩阻力沿桩长大致呈"S"型分布,其桩顶以下1/6桩长范围内侧摩阻力远远大于直桩。

In recent years, inclined pile has been widely used in foundation engineering like the bridge piers, offshore drilling platforms, and large transmission line tower.It is of great practical significance to study the load transfer and bearing characteristics of inclined piles with different angles.The bearing characteristics of different inclined piles were simulated and analyzed considering the pile-soil contact characteristics using the ABAQUS software.The finite element analysis results show that： When pile inclination was less than 10°, inclined angle of the single pile has neglectable effect on ultimate bearing capacity.But it may produce a certain bending moment in the body of the pile and a certain lateral displacement on top of the pile;Decay rate of axial force alone the length of piles increased as inclination increased;The bending moment of the pile shaft mainly occur in the lower one-halfof pile length.Inclination of batter piles and vertical load had no effect on the position where the maximum appears;The inclined pile skin friction along the pile length shows ＂S＂ type distribution.The skin friction of the inclined pile in the long range of 1/6 pile was far greater than that of the vertical pile under the pile head.