微型桩-锚组合抗滑新结构支挡效果的数值分析  

Numerical Analysis of Retaining Effect Surported by New Micropile-Anchor Composite Anti-sliding Structure

作　　者：胡田飞[1,2] 杜升涛 梁龙龙 

机构地区：[1]中国铁道科学研究院,北京100081 [2]中铁西北科学研究院有限公司,兰州730000

出　　处：《防灾减灾工程学报》2015年第2期212-218,共7页Journal of Disaster Prevention and Mitigation Engineering

基　　金：科技部科研院所技术开发研究专项资金项目(2009EG123201)资助

摘　　要：针对微型桩加固滑坡时抗弯强度不足的缺陷,在类叉形微型桩组合结构的基础上引入预应力锚索,提出了一种微型桩-锚组合抗滑新结构。为验证其加固效果,基于斜坡应力状态变化理论,利用有限差分软件FLAC3D,分析了某边坡处于临滑状态时有无微型桩-锚结构加固的变形位移及应力分布特征。结果表明:1滑动状态下,坡体下部位移、应力水平大于上部,判断为牵引式滑坡;2新结构在布设位置产生较大局部应力集中,形成了一个结构-土空间骨架结构,在复合体系作用下滑坡体位移及中下部应力集中得到有效控制,尤其是在坡脚附近,主应力差、剪应变增量明显减小;3预应力锚索可以有效改善结构的整体受荷能力并减小桩身弯矩峰值;4该新结构轻型、环保、抗弯承载力高,可较好地满足边坡病害快速治理工程的需要。Aiming at the defects of the mieropile that the bending strength is insufficient when strengthening the landslide,this paper introduces prestressed anchor on base of the fork-like mi- cropile composite structure,and puts forward a new micropile-anchor composite anti-Miding struc- ture. In order to verify the reinforcement effect, on the base of the theory of slope stress state, this paper uses software FLAC3D to analyze the deformation displacement and stress distribution characteristics of the slpoe in critical sliding state when reinforced by the new micropile-anchor composite structure or not. Comparative results show that：（1） in sliding state, displacement and stress levels of the lower part of slope are greater than those of the upper, judging for the tractive landslide; （2）larger local stress concentration occurs at the arrangement location of the new structure, forming of a structure-soil space frame structure; landslide movement and stress con- centration in the middle and lower parts are controlled effectively by the composite system, espe- cially near the slope toe, the principal stress difference and shear strain increment are obviously reduced; （3） prestressed anchorage cable can improve the bearing capacity of the overall structure and decrease the peak of the pile bending moment effectively; （4）the new structure is light, green, and of high flexural bearing capacity, can meet the need of quick treatment against slope disease.

关 键 词：微型桩 锚索 组合结构 边坡 FLA^3D 位移 应力 

分 类 号：U455.71[建筑科学—桥梁与隧道工程]