铁路隧道斜穿滑坡体受力变形特征三维分析

Three-dimensional Analysis of Force and Deformation Characteristics of Oblique Crossing of Railway Tunnel with Landslide

研究目的:在工程实践中,因选线空间及线型条件受到限制,铁路隧道必须穿越滑坡体并将隧道洞门设置于滑坡上。目前已有的研究大多基于理论上的二维模型分析,而对于隧道–滑坡体斜交情形,建立真三维模型能更真实地反映隧道与滑坡体的相互作用和结构受力变形特征。本文以甘钟铁路洛阳村隧道改线工程右嘴头隧道进口滑坡治理项目为背景,应用MIDAS GTS有限元计算软件建立滑坡、抗滑桩、隧道三维空间模型,模拟抗滑桩施工、路基及隧道洞身开挖支护施工过程。从数值计算结果中提取各施工步骤抗滑桩、隧道结构的受力变形数据,研究铁路隧道斜向穿越滑坡体时的受力变形特征,以及隧道洞身开挖对滑坡稳定的影响过程。研究结论:(1)隧道洞身在滑体和滑床中的受力特征分别表现为偏压和围压;(2)隧道结构纵向变形主要位于滑带附近隧道结构;(3)当隧道洞身开挖完全进入滑床段时,对滑坡的稳定及抗滑桩受力影响逐渐消失。

Research purposes： In engineering practice, due to the concept of space and linear constrained conditions, railway tunnel must be through the landslide and the tunnel portal must be set on the landslide. The existing relevant research results are mostly based on the two - dimensional model of theory analysis. When the railway tunnel and landslides oblique, true 3D model can reflect interaction and structure deformation characteristics of the tunnel and landslide more truly. Taking Youzuitou landslide renovation of the Luoyangcun tunnel rebuilding project of Ganquan - Zhongjiacun railway as the background, MIDAS GTS finite element software is used to establish three - dimensional model of landslide, anti -slide pile, tunnel and simulate anti -slide pile construction, the roadbed and the tunnel hole excavation supporting construction process. Extracted from the results of numerical calculation of each construction step, the stress of the tunnel structure and anti - slide pile deformation data are used to study stress deformation characteristics of railway tunnel while the railway tunnel oblique crossing with landslide and the influence of tunnel excavation on the landslide stability process.Research conclusions： （ 1 ） The stress characteristics of tunnel in the sliding body and sliding bed respectively show the bias and confining pressure. （2） The longitudinal deformation of tunnel structure is mainly focused on the sliding zone nearby. （3）The hole body of tunnel is completely excavated and anti -slide force gradually disappear. the slide bed, the influence on the stability of landslide