【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。更多还原

【Abstract】 Aiming at the defects of the micropile that the bending strength is insufficient when strengthening the landslide,this paper introduces prestressed anchor on base of the fork-like micropile composite structure,and puts forward a new micropile-anchor composite anti-sliding structure.In order to verify the reinforcement effect,on the base of the theory of slope stress state,this paper uses software FLAC3 Dto 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 concentration in the middle and lower parts are controlled effectively by the composite system,especially 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.更多还原