抗滑桩加固斜坡软弱地基路堤的数值模拟

在路堤荷载作用下，斜坡软弱地基易产生侧向变形过大、滑塌失稳等病害。路堤下坡脚处采用钢筋混凝土抗滑桩，以有效限制地基侧向变形，是斜坡软弱地基路堤的核心设计原则。采用三维快速拉格朗日有限差分法，经与室内土工离心模型试验成果对比、校核，建立抗滑桩加固斜坡软弱地基路堤的精细化数值分析模型，研究抗滑桩桩距、桩长、桩身弹性模量、桩身横截面尺寸及桩位等设计参数对其内力、变位的影响。研究表明：下坡脚处实施抗滑桩可显著约束斜坡软弱地基侧向变形；需综合考虑桩身受力、经济性、施工等因素确定合理的桩距；桩长应深入滑移面以下，但随着桩长的增长，加固效果增长不明显；随着桩身弹性模量、桩身横截面尺寸的增加，抗滑桩的加固效果得到一定提高；抗滑桩宜设置在下坡侧路堤边坡的中部。

Numerical simulation of embankment on sloped weak ground reinforced by anti-slide piles

Sloped weak ground under the load of the embankment easily triggers major engineering accidents such as large lateral deformation and slump.It is the core design principles of embankment on sloped weak ground that application of reinforced by concrete anti-slide pile at the corner of embankment can effectively limit lateral deformation of the foundation.This paper studies the influence of the pile design parameters such as pile spacing,pile length,elastic modulus,cross-section dimension and the position of piles on its internal forces and deformation by using 3D fast Lagrangian analysis of continua,comparing with the results of indoor geotechnical centrifugal model tests,and building precise numerical analysis model of embankment on sloped weak ground reinforced by anti-slide piles.Research results show that,using anti-slide piles at the downhill toe of embankment could significantly restrict the lateral deformation of sloped weak ground.It will comprehensively consider the factors such as force,economy,construction etc.in order to confirm the reasonable pile spacing;anti-slide piles must penetrate potential slip surface,but with the increase of the length of pile,the reinforcement effect does not significantly increase;with the increase of elastic modulus,cross-section dimension of pile,the reinforcement effect is improved in some extent;anti-slide pile is suitable to set at the middle of bypass downhill slope of the embankment.