空间弧形抗滑桩支护结构模型试验及参数分析

Model test and parameter analysis of spatial arc antislide structure

为充分利用边坡滑体周围的稳定土体,改善抗滑桩受力状态,本文通过室内模型试验,对空间弧形抗滑桩支护结构的受力状态、荷载传递规律和桩前土压力进行分析;并建立有限元模型,考虑冠梁刚度和桩位对抗滑桩受力状态和边坡整体稳定性的影响。结果表明:在整个支护结构中,冠梁可约束抗滑桩,改善抗滑桩受力状态,协调桩间位移,并将荷载向两侧桩体传递;通过增大冠梁刚度可进一步改善桩体受力状态,但无法进一步约束桩顶位移;边桩桩前土压力最大,其峰值是其他桩体土压力峰值的2倍以上,沿桩身高度不断增大,抗滑结构中的边桩位于坡脚时,可最大程度利用稳定土体的抗力,边坡整体稳定性最强。研究结果可为滑坡的治理方法以及抗滑桩支护结构的优化提供一种基本可行的新思路。

We analyze the mechanical characteristics,force transferring law,and passive earth pressure of antislide piles on the basis of laboratory model test and established finite element models to make full use of the soil around the sliding body of a slope and improve the mechanical state of antislide piles.We take into account the influences of coupling beam stiffness and pile position on the mechanical state of antislide piles and slope stability.Results show that coupling beams can constrain antislide piles,coordinate the displacement of pile tops,improve the mechanical state of antislide piles,and transfer load from the piles at the arch roof to the arch foot.Increasing coupling beam stiffness can further improve the mechanical state of the piles but has a limit to constraining the displacement of the pile top continuously.The passive earth pressure in front of the piles at both sides of the antislide structure increases with the increase in the height of the pile section.Its largest value is more than two times the peak earth pressure of other piles.When the piles at the arc foot are fixed on the slope foot,the resistance of stable soil can be utilized to the greatest extent,and the slope safety is the best.The results of this research can provide a feasible new idea for the landslide treatment and optimization of antislide structures.