滑坡抗滑短桩的受力特性模拟研究

Numerical simulation for mechanical characteristics of short anti-sliding pile

摘要:

抗滑短桩是滑坡常用的治理措施之一，应用较为广泛，但其承载机理尚不清晰。采用FLAC^3D模拟程序建立不同长度抗滑短桩加固滑坡的数值模型，分析滑坡模型变形特征以及抗滑短桩受力特性，进一步揭示抗滑短桩加固滑坡的受力特性。研究结果表明：（1）不同长度的抗滑短桩可显著提高滑坡的整体稳定性；（2）随着抗滑短桩桩长的增加，桩身受力趋于均匀，桩-土协同作用增强，滑体最大位移逐渐降低，但降低速率减小；（3）自由段桩长与滑体厚度比值<0.6时，滑坡出现“越顶”破坏现象；（4）建议抗滑短桩的自由段长度与滑体厚度比值取为0.7~0.9。

Abstract:

Short anti-sliding pile is widely used as the common treatment measures to landslide， however， its bearing mechanism is not clear. In this paper， the software of Fast Lagrangian Analysis of Continua in 3 Dimension （FLAC^3D） is used to build numerical model of anti-sliding piles to reinforce landslides with different length， the characteristics of deformation of the landslide model and the mechanics of the anti-sliding piles are analyzed， and the mechanics to reinforce the landslide is further revealed. The results show that： （1）the stability of the slope can be increased obviously with the reinforcement by short anti-sliding pile with different length； （2） with the increase of the short pile length，the stress of the pile spreads more evenly， and the integrity of the pile and soil is better， the maximum displacement of slope is reducing with lower reduce rate； （3）The slope destroyed cross over the pile when the ratio of the pile’s free section length to the thickness of the landslide is less than 0.6； （4）the ratio of the pile’s free section length to the thickness of the landslide is suggested to be 0.7~0.9.