复合土钉支护内力与变形的模拟分析  

Simulation analysis of stress and deformation of compound soil nailing

作　　者：赵延林[1] 曹洋[1] 高红梅[1] 马强[1] 

机构地区：[1]黑龙江科技学院建筑工程学院,哈尔滨150027

出　　处：《黑龙江科技学院学报》2009年第6期486-489,共4页Journal of Heilongjiang Institute of Science and Technology

基　　金：黑龙江省教育厅科学技术研究项目(11521255);哈尔滨市科技创新人才研究专项资金项目(2008RFQXS109)

摘　　要：为研究复合土钉支护体系中各构件的协同作用机理,应用FLAC-3D软件对纯土钉支护、土钉-预应力锚杆支护、土钉-微型桩-预应力锚杆支护三种支护方式进行模拟分析。结果表明:锚杆的深层锚固作用使各层土钉的轴力相对于纯土钉支护明显减小,且距离锚杆越近的土钉轴力下降越明显;预应力锚杆的挤压作用使土体的可能滑裂面后移,滑移半径增大,基坑边坡的稳定性增强;微型桩的设置,增强了其周围一定范围内土体的强度,改善了开挖后土体的应力场和边坡的稳定性;设置微型桩超前支护后,土钉及预应力锚杆的轴力均下降,但下降幅度不大;在土钉支护中相继增加预应力锚杆和微型桩后,基坑的水平位移明显减少。Aimed at studying the mechanism of synergistic action of all structural units in composite soil nailing supporting system, this paper introduces the simulation and analysis of the soil nailing supporting system, the soil nailing ＆ prestressed anchor supporting system and the soil nailing ＆ micro-pile ＆ pre- stressed anchor supporting system with FLAC -3D. The results show that the deep anchoring action of anchor shows more obvious decrease in the axial force of soil nailing by composite soil nailing supporting system than by soil nailing supporting system, and the soil nailing closer to the anchor shows more obviously decreased axial force. Backward movement of the potential gliding plane due to the extruding action of prestressed anchor gives the enlarged gliding radius and resulting enhancement in the stability of the sides of foundation pit. The micro-pile increasing the strength of soil around it within a certain range betters the stress field of soil after excavation and the stability of sides of foundation pit. As an advancing support, the arrangement of the micro-pile is followed by the slight reduction in the axial force of soil nailing and anchor, but the reducing amplitude is not large. The prestressed anchor and the micro-pile, put into the soil nailing supporting system results in decreases in the horizontal displacement of foundation pit.

关 键 词：复合土钉 预应力锚杆 微型桩 数值模拟 

分 类 号：TU473.2[建筑科学—结构工程]