土体侧移作用下轴向受荷单桩承载性状数值分析

3D Numerical Analysis for Behavior of Axially Loaded Pile Subjected to Lateral Soil Movement

摘要:

地下工程开挖引起的土体侧移对邻近轴向受荷桩的承载和变形性状可能会产生负面影响,对于这一问题目前还缺乏充分的研究.采用有限差分软件FLAC 3D(fast Lagrangian analysis of continua 3D)进行分析,讨论轴向受荷桩在土体侧移作用下的承载和变形特性,重点分析了土体强度、桩身刚度以及桩顶不同约束条件下的单桩性状.数值分析表明,在竖向荷载和侧向土体位移耦合作用下,轴向荷载的增加或者侧向位移的变大,对桩身变形和弯矩有着明显的影响,而土体强度、桩身刚度以及桩顶约束条件也会对桩的受力特性产生不同程度的影响,在工程实践中应予以充分重视.

Abstract:

The construction of underground works or tunnel excavation will lead to the displacement of the surrounding soil.Lateral soil movements and load mostly have a negative influence on the bearing characteristics of axially loaded piles.The finite difference software FLAC 3D is adopted to analyze the behavior of axially loaded piles subjected to lateral soil movement.The effects of soil strength,pile bending stiffness and pile head constraint on the response of pile are analyzed.The results from the numerical analysis show that the increase of the lateral soil movements and/or the axial load will greatly influence the bending moment and deflection of the axially loaded pile.The behavior of the axially loaded pile is also affected by different soil strength,pile bending stiffness and pile head constraint.Therefore,the coupling effect of lateral soil movement and axial load can not be ignored in practical pile design.