【作者】 张鑫；

【导师】 樊怀仁；

【作者基本信息】 西安科技大学 ， 地质工程， 2010， 硕士

【摘要】 近年来,随着我国高速公路和高等级公路的迅速发展,公路隧道建设已进入大发展的新时期,相应地对公路隧道特别是长大隧道建设技术提出了更高的要求。公路隧道施工过程中,洞室周围岩体发生应力重分布作用,当这种重分布应力超过围岩的强度极限时,将造成围岩的失稳破坏。围岩稳定性评价是公路隧道施工中极为重要的研究内容。在地质条件复杂的西部山区,由于稳定性影响因素及其权重的差异,评价方法体系的建立以及评价结果的筛选、分析等需要视具体情况做针对性的研究。本文结合阿荣旗～北海高速公路万源至达洲段大巴山隧道工程实例,以高速公路隧道围岩稳定性评价为主线,采用定性评价和定量评价、整体评价和局部评价相结合的方法,对隧道围岩稳定性展开了系统的研究。首先,从影响隧道围岩稳定性的工程地质因素入手,对围岩的变形破坏机制进行了分析和探讨。针对结构面和薄夹层发育且围岩具有弹塑性性质的地质特征,提出强度—应力控制型是大巴山隧道围岩最主要的变形破坏机制,破坏方式表现为顶拱部位的张裂塌落和劈裂剥落破坏;其次,针对大巴山隧道特定的工程地质条件,从围岩分级、监控量测两方面入手,对隧道围岩进行稳定性综合评价。确定了大巴山隧道围岩类别为III类、IV类、V类围岩;最后,通过对隧道施工过程中围岩稳定性的深入分析,利用二维弹塑性有限单元法对隧道IV类围岩段在两种不同施工方案下施工过程中围岩稳定性和安全性进行分析,研究施工过程中围岩的位移、应力变化规律,为隧道进行合理的初期支护设计和施工提供了参考,对隧道设计和施工有指导意义。更多还原

【Abstract】 In recent years, with the rapid development of the expressway and highway of our country, highway tunnel has entered the new period of great development, which promotes higher requestion to build technology of highway tunnel, especially the long or big section highway tunnel.In the course of the expressway tunnel’s construction, the stress in rock mass will redistribute around grotto. When this kind stress exceeds surrounding rock ultimate strength, surrounding rock will lose its stability and destruct. Stability analysis of surrounding rock is a momentous science research correlated with the expressway tunnel’s construction. Particularly in the western mountainous areas with complx geological conditions, because of the diference of the influeneing factors and weight of it, to establish the methods system and analysis the evaluation result must be researched specially.Associated with the project of Dabashan tunnels, which is part of the Arongqi to Beihai highway, sticking to the evaluation of surrounding rock’s stability and direct highway tunnel’s construction, with the combination of qualitative evaluation, quantitative evaluation, integrate and local evaluation, the surrounding rock’s stability of tunnels is studied systematically.Firstly, with the engineering geological factors influencing surrounding rock’s stability of tunnel, the paper carries on the analysis and discussion about deformation and destruction mechanism to surrouding rock.According to structural surface development and elastic-plastic geological characteristics, intensity-tress control type is put forward. And the top arch is the weak point.Secondly, according to the specific engineering geological conditions of Dabashan tunnel, using surrounding rock classification, monitoring measurement, to evaluate the stability of tunnel surrounding rock. The classification is divided into three types: III surrounding rock, IV surrounding rock and V surrounding rock. Finally, based on the analysis of the basic theory about the interaction mechanism of the surrounding rock in construction, a numerical computation method with 2-D elastic-plastic finite element is proposed to analyze stability and safety of the IV surrounding rock in construction, through analyzing the distributing law of displacement. Dispelled the danger in construction process in order to prevent before the occur, and has significance in guiding the design and construction of tunnel.更多还原