隧道上覆溶洞突涌水机理与安全厚度预测及工程应用

发布时间：2018-02-09 11:47

本文关键词： 充水溶洞孕灾模式数值计算最小安全厚度软件设计工程应用　出处：《山东大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着隧道及地下工程的大量修建,岩溶灾害问题日益严重,其中溶洞突涌水一直是岩溶隧道建设过程中的最严重的地质灾害之一,突涌水极易造成隧道工期延误、器械报废、人员伤亡。针对上述事实,通过理论分析、数值计算和软件设计手段对溶洞与隧道间最小安全厚度进行研究,以期对隧道建设提供有利的应用价值,主要内容如下：(1)总结充水溶洞赋存规律及孕灾模式。通过对已有的相关文献分析和总结,归纳出充水溶洞的地质赋存规律及充水性规律,初步分析了充水溶洞的孕灾模式,主要从涌水量与破坏通道两方面进行因素总结,充水溶洞的破坏力往往离不开其涌水量及破坏通道的形成,基于充水溶洞的破坏方式,分别根据地质前兆、力学前兆以及地球物理场前兆,归纳了孕灾性识别。(2)建立三维含充水溶洞隧道数值模型,初探溶洞与隧道间最小安全厚度判据。采用大型数值计算软件Ansys10.0,建立了三维含球体充水溶洞的隧道数值模型,并设置一些列物理力学参数,形成多级工况,利用FLAC3D软件渗流模式进行隧道开挖收敛计算,通过数值计算可以揭示隧道围岩力学信息在充水溶洞的赋存情况下随开挖的变化规律,同时也获得溶洞与隧道间最小安全厚度的结论。(3)设计一款基于数值计算结果的最小安全厚度预测软件系统。利用Microsoft Visual C++平台设计了一款集最小安全厚度预测与突涌水灾害预警软件系统,基于数值计算结果,通过一元回归和多元回归建立了溶洞与隧道间最小安全厚度预测数学模型,其中围岩级别因素设计有专门的评价模块,围岩级别是通过层次分析法以及专家打分原则进行的,综合考虑了主观性和客观性,使用两个工程案例对软件系统进行了验证,其结果与现场开挖具有较高的一致性。
[Abstract]:With the construction of tunnel and underground engineering, the karst disaster is becoming more and more serious, among which, the karst cave water gushing is one of the most serious geological disasters in the construction process of karst tunnel. The sudden water gushing easily causes the tunnel construction period to be delayed and the equipment to be scrapped. According to the above facts, through theoretical analysis, numerical calculation and software design, the minimum safe thickness between cavern and tunnel is studied in order to provide beneficial application value for tunnel construction. The main contents are as follows: (1) summing up the occurrence law and disaster prevention model of water-filled karst cave. Through the analysis and summary of the relevant documents, the geological occurrence law and water-filling law of water-filled karst cave are summarized, and the disaster prevention mode of water-filled karst cave is analyzed preliminarily. The main factors are summarized from two aspects of water inflow and damage channel. The destructive power of water-filled karst cave is often inseparable from its water inflow and the formation of damage passage. Based on the failure mode of water-filled karst cave and the geological precursor respectively, The mechanical precursor and geophysical field precursor are summed up to identify the disaster preparedness. (2) A three-dimensional numerical model of water-filled cavern tunnel is established. This paper deals with the criterion of minimum safe thickness between caverns and tunnels. A numerical model of a three-dimensional tunnel with spherical water-filled caverns is established by using the large-scale numerical calculation software Ansys 10.0, and some physical and mechanical parameters are set up to form multistage working conditions. The convergence calculation of tunnel excavation is carried out by using FLAC3D software seepage model. Through numerical calculation, the variation law of mechanical information of surrounding rock with excavation can be revealed under the condition of the existence of water-filled caverns. At the same time, the conclusion of minimum safe thickness between cave and tunnel is obtained. (3) A software system for predicting minimum safe thickness based on numerical calculation results is designed. A set of minimum safe thickness prediction and burst is designed by using Microsoft Visual C platform. Water gushing disaster early warning software system, Based on the results of numerical calculation, a mathematical model for predicting the minimum safe thickness of caverns and tunnels is established by univariate regression and multivariate regression, in which the design of surrounding rock grade factors has a special evaluation module. The grade of surrounding rock is carried out by AHP and expert scoring principle. Considering subjectivity and objectivity, the software system is verified by two engineering cases, and the results are in good agreement with the excavation on site.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U453.61

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