基于透明土的不同间、排距抗滑桩边坡滑移特征

Sliding characteristics of anti-slide pile slopes with different pile spacing and row spacing based on transparent soil

为探讨不同间、排距抗滑桩支护下边坡的滑移规律和特征,采用透明土模型试验并结合粒子图像测速技术,进行不同间、排距抗滑桩加固下边坡透明土试验,以探讨坡顶受荷下抗滑桩边坡土体的整体移动规律和滑移破坏特征。通过不同间、排距抗滑桩加固边坡土体的位移矢量图、位移等值线图以及荷载-位移曲线特征分析。结果表明:抗滑桩边坡的滑移过程可分为稳定、匀速和加速变形3个阶段,边坡极限承载力随桩间、排距的减小有所增大;抗滑桩加固边坡的滑动层深度随桩间、排距的扩大而加深,间、排距为3 b时,出现坡面浅层和桩身中部位置的两个深浅不一的滑动面,表现为越顶剪切和桩土体系共同倾覆破坏。基于研究结论,对边坡防护提出以下建议:对于重要边坡防护工程,方形抗滑桩间、排距不宜超过桩截面边长的3倍和4倍,对于承载力要求不高的边坡工程,可适当增加桩间、排距以减小施工成本。

In order to study the sliding process and characteristics of slopes supported by anti-slide piles with different pile spacing and row spacing,transparent soil model test combined with PIV digital image processing technology was adopted to conduct tests on the transparent soil of slope reinforced by anti-slide piles with diffe-rent pile spacing and row spacing,so as to study the displacement law and sliding failure characteristics of anti-slide pile slope soil under load at the top of the slope.The displacement vector diagram,displacement contour map and load-displacement curve characteristics of slope soil reinforced by anti-slide piles with different pile spacing and row spacing were analyzed.Results show that the sliding process of the anti-slide pile slope can be divided into three stages:stable,uniform,and accelerated deformation.The ultimate bearing capacity of the slope increases with the decrease of the pile spacing.The depth of the sliding layer of the slope deepens with the increase of pile spacing and row spacing.When the spacing is 3 b,there are two sliding surfaces with different depths in the shallow layer of the slope and the middle of the pile body,manifested as the joint overturning failure of the top shear and pile soil system.Based on the research conclusions,the following suggestions are put forward for engineering applications.Firstly,for important slope protection projects,the pile spacing and row spacing of square anti-slide piles should not exceed 3 and 4 times the side length of the pile section.Secondly,for slope engineering with low bearing capacity requirements,the pile spacing and row spacing can be appropriately increased to reduce construction costs.