水泥土连拱抗滑墙加固软基边坡机理研究

针对传统的复合地基加固软基边坡时水泥土桩身易拉裂破坏和弯折破坏的问题,为更好地发挥水泥土高抗压强度的特点,对新型边坡加固结构水泥土连拱抗滑墙设计并实施了大比例模型试验。分析了各级荷载下软硬土层所分担的水平推力,发现水泥土连拱抗滑墙能够有效地把推力传递到下层硬土中。采用有限差分软件FLAC3D对水泥土连拱抗滑墙与水泥土搅拌桩复合地基两种边坡加固结构进行数值模拟,分析了水平应力、剪应力的分布情况及土体塑性区分布的对比,比较两者的加固效果。结果表明,在相同条件下,复合地基中的水泥土桩易发生弯折,水泥土连拱抗滑墙能够有效发挥水泥土抗压性能,避免桩身出现拉裂破坏和弯折破坏。水泥土连拱抗滑墙加固效果明显优于水泥土搅拌桩复合地基。

Action Mechanism of the Application of Cement-soil ArchedWalls in the Anti-slide Reinforcement of Soft Ground Embankment

For the reason that cement-soil pile is prone to tensile crack failure and flexural failure in the traditional composite foundation and give the compressive strength of cement-soil into full play, this paper designed and implemented large-scale model tests on the application of cement soil arched walls in the anti-slide reinforcement of soft ground embankment which analyzed the horizontal thrust that soft and hard layer sharing under different load levels. It is showed that the cement-soil arched walls could effectively transfer the thrust to the hard soil layer. The numerical simulation were implemented on the two kinds of slope reinforcement structure to gained more information which were difficult to measure in the model test. The distribution of horizontal stress and shear stress is analyzed and the comparison of soil plastic zone distribution. The results show that under the same conditions, the cement-soil piles of composite foundation are easy to bend and the cement-soil arched walls can give the compressive strength of cement-soil into full play which avoiding tensile crack failure and flexural failure. The reinforcement effect of cement-soil arched walls is better than soil-cement piles composite foundation.