隐伏溶洞对隧道围岩稳定性的影响规律及鄂西山区岩溶处治技术研究

发布时间：2018-03-16 07:46

本文选题：岩溶隧道　切入点：隐伏溶洞　出处：《山东大学》2014年硕士论文　论文类型：学位论文

【摘要】：岩溶隧道突水突泥等地质灾害给隧道施工和运营安全造成极大威胁,已引起国内外的广泛关注。如何针对不同地质条件下不同类型的岩溶隧道采用恰当的岩溶治理措施来减轻隧道岩溶危害是一个亟待解决的重大难题。鄂西山区多为碳酸盐岩地层,气候湿润,导致地表多形成岩溶洼地,山体内溶洞、溶腔、地下暗河等岩溶构造十分发育,隧道建设过程中极易遇到不同类型、不同分布形态的隐伏溶洞。溶洞的大量存在,极易导致隧道在开挖扰动下发生大规模的突水突泥、隧道围岩崩塌、地表塌陷等地质灾害,对施工安全构成严重威胁。为此,研究溶洞的发育特征及规律,分析不同类型溶洞对隧道围岩稳定性的影响,建立一套行之有效、经济合理的隧道溶洞综合治理方案和体系,从根本上解决具有隐蔽性和突发性的岩溶危害问题,不仅对既有岩溶地区隧道施工具有重要技术价值和经济意义,而且为在建和待建的岩溶隧道的建设提供了重要的理论依据和现实指导。本文以鄂西山区恩来恩黔高速公路、利万高速22条岩溶隧道为工程背景,探讨了岩溶发育机制及特征,建立了鄂西山区隐伏溶洞分类体系,基于层次分析法,定性研究了鄂西山区高速公路含隐伏溶洞岩溶隧道围岩稳定性的影响因素与因素权值,并提出了隐伏溶洞影响隧道围岩稳定性的评估方法。基于COMSOL Mutiphysics多场耦合数值模拟软件定量分析了在不同类型和分布形态下的隐伏溶洞的影响下隧道围岩渗流场、应力场及位移场的变化规律,探究不同施工步骤、围岩等级、距离、水压、大小、形状以及位置的隐伏溶洞对隧道稳定性的影响。结合鄂西山区岩溶隧道实际施工情况,针对不同类型的隐伏溶洞提出了具体的治理原则和处治技术。本文开展主要研究工作如下： (1)系统收集国内外典型溶洞工程案例资料,基于岩溶发育的四项基本条件,结合鄂西山区高速公路项目群,研究鄂西山区岩溶发育特征规律及分类特征,将恩来恩黔高速、利万高速22条岩溶隧道揭示的隐伏溶洞综合分类。 (2)基于鄂西山区隐伏溶洞发育条件,综合施工因素和控制措施,筛选出隐伏溶洞对隧道围岩稳定性影响的评估指标,采用层次分析法,建立含隐伏溶洞的隧道围岩稳定性评估模型,为溶洞的治理提供定性理论依据。 (3)基于隐伏溶洞对隧道围岩稳定性影响因素的研究,利用COMSOL Multiphysics数值模拟软件研究在不同类型和分布形态的隐伏溶洞影响下隧道围岩渗流场、应力场及位移场的变化规律,揭示含隐伏溶洞隧道围岩失稳机理,为溶洞的治理提供理论依据。 (4)结合恩来恩黔高速公路的工程实例总结溶洞处治原则与处治技术,针对不同类型的溶洞分别提出合理的处治措施。
[Abstract]:Geological disasters such as water inrush and mud outburst in karst tunnels pose a great threat to the safety of tunnel construction and operation. How to adopt appropriate karst treatment measures for different types of karst tunnels under different geological conditions to reduce tunnel karst hazards is a major problem to be solved urgently. Carbonate strata, The humid climate leads to the formation of karst depressions on the surface. Karst structures such as caves, caverns and underground rivers are well developed. During the construction of tunnels, it is easy to encounter different types of concealed caverns with different distribution forms. A large number of karst caverns exist. It is easy to cause large-scale water inrush and mud inrush under excavation disturbance, the surrounding rock collapse of tunnel, surface collapse and other geological disasters, which pose a serious threat to the safety of construction. Therefore, the development characteristics and rules of karst cave are studied. This paper analyzes the influence of different types of caverns on the stability of tunnel surrounding rock, establishes a set of effective and reasonable comprehensive treatment scheme and system of tunnel caverns, and fundamentally solves the problem of karst hazards with concealment and sudden occurrence. It not only has important technical value and economic significance for tunnel construction in existing karst areas, but also provides important theoretical basis and practical guidance for the construction of karst tunnel under construction and pending construction. In this paper, 22 karst tunnels in Liwan high speed are studied, the karst development mechanism and characteristics are discussed, the classification system of concealed karst caves in western Hubei is established, and the classification system is based on the Analytic hierarchy process (AHP). In this paper, the influence factors and weights of surrounding rock stability of karst tunnel with concealed caverns on expressway in western Hubei mountain area are studied qualitatively. Based on the COMSOL Mutiphysics multi-field coupled numerical simulation software, the seepage field of the tunnel surrounding rock under the influence of different types and distribution forms is analyzed quantitatively. The variation law of stress field and displacement field, the influence of different construction steps, surrounding rock grade, distance, water pressure, size, shape and position on the stability of tunnel is discussed. Specific treatment principles and treatment techniques are put forward for different types of hidden caverns. The main research work of this paper is as follows:. Based on the four basic conditions of karst development and combined with the expressway project group in the west of Hubei province, the characteristics of karst development and the classification characteristics of karst development in western Hubei mountain area are studied systematically, and the high speed of Enlai and Guizhou is put forward. Comprehensive classification of hidden karst caves revealed by 22 karst tunnels in Liwan high speed. (2) based on the development condition of concealed karst cave in western Hubei mountain area and the comprehensive construction factors and control measures, the evaluation index of the influence of hidden karst cave on the stability of surrounding rock of tunnel is screened out, and the analytic hierarchy process is used to evaluate the influence of hidden karst cave on the surrounding rock stability. The evaluation model of surrounding rock stability of tunnel with hidden caverns is established to provide qualitative theoretical basis for the treatment of caverns. 3) based on the study of the influence factors on the stability of tunnel surrounding rock, the variation of seepage field, stress field and displacement field of tunnel surrounding rock under the influence of different types and distribution forms of hidden karst cave are studied by COMSOL Multiphysics numerical simulation software. The mechanism of surrounding rock instability of tunnel with concealed caverns is revealed, which provides theoretical basis for the treatment of karst caves. 4) combining with the engineering example of Erlaien and Guizhou Expressway, summarizes the principles and techniques of karst cave treatment, and puts forward reasonable treatment measures for different types of karst cave respectively.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U451.2;U455.49

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