岩溶隧道地基沉降计算方法研究

发布时间：2018-03-08 11:47

本文选题：岩溶隧道　切入点：概化模型　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：近年来,我国交通运输业的运营需求与日俱增,高速铁路事业得以蓬勃发展,众多的铁路隧道在西南片区岩溶发育的地层中修建,岩溶地质灾害给隧道施工建设和运营维护带来了艰巨的挑战。鉴于岩溶发育的不确定性以及岩溶隧道的复杂性,目前对岩溶隧道的研究程度尚不足以满足工程建设的需要。为此,本文以云桂铁路长庆坡隧道大型岩溶为研究对象,建立了充填性岩溶隧道概化模型,利用FLAC3D计算软件,研究充填性岩溶的边界范围对隧道基底在列车荷载作用下的沉降影响规律,并通过数据分析,得到基于敞开地基沉降计算的隧道基底沉降计算方法。论文的主要工作内容如下:(1)查阅前人研究资料,就国内外岩溶顶板安全厚度和稳定性、岩溶大小和分布位置对隧道影响方面的研究现状进行总结概括。(2)以云桂铁路长庆坡隧道大型岩溶为研究背景,对岩溶与隧道的空间关系进行了分析,并概括为三种模型,最后在此基础上建立岩溶隧道概化模型。(3)利用数值计算软件建立岩溶隧道分析模型,分别研究了岩溶上下边界和左右边界范围对隧底加载沉降的影响。结果表明,岩溶左右边界影响范围为2d(d为隧道直径),下边界的影响范围为3d,上边界的影响范围为1.2d;岩溶位于隧道基底以下时,隧道底板安全厚度应不小于5m;侧部岩溶会导致隧道该侧围岩产生应力集中,且随着距离越近,应力集中程度越大。(4)当岩溶存在于隧道平面有限范围内时,将岩溶的边界参数进行整合,研究其综合影响,并分别命名为上下轴。最终模拟结果表明,上轴的最大影响范围为1.6d,最小影响范围为-0.5d;下轴的最小影响范围为-3.1d。当岩溶底边界超过基底面时,岩溶对隧道基底加载影响较小,但隧道围岩受岩溶影响不可忽略。(5)基于数值模拟计算结果,采用1stOpt数据拟合软件,建立了考虑岩溶边界影响的岩溶隧道地基沉降理论计算方法,并运用图形化编程软件Lab VIEW实现了计算流程的界面化和程序化。针对某具体岩溶隧道实例,运用本文设计的基底沉降计算程序,与实例中隧道基底沉降计算值进行对比分析,验证了所提方法的合理性。
[Abstract]:In recent years, China's transportation industry is the operational requirements of high-speed railway enterprises to grow with each passing day, the vigorous development of railway tunnel construction, many of the development in the southwest area of karst formation, brought huge challenge to the karst geological disaster of tunnel construction and operation and maintenance. In view of the uncertainty of karst development and the complexity of karst tunnel. The present study degree of karst tunnel is still not enough to meet the needs of engineering construction. Therefore, based on the cloud Guangxi railway Changqing large karst Slope Tunnel as the research object, the establishment of the filling karst tunnel conceptual model, using the FLAC3D calculation software, the filling karst boundary of tunnel foundation under train loads settlement influence, and through data analysis, get the open foundation settlement of tunnel base settlement calculation method based on the main contents of this paper are as follows: (1) Review of previous studies, both at home and abroad and the safe thickness of karst roof stability of karst, the size distribution and the position of the research summarized the tunnel effect. (2) to cloud Guangxi railway Changqing large karst Slope Tunnel as the research background, the spatial relationship of karst tunnel are analyzed, which are summarized as three kinds of models finally, on the basis of the establishment of karst tunnel model. (3) establish the calculation software of karst tunnel by numerical analysis model, the effect of loading on the karst border of the tunnel bottom settlement were studied. The results indicate that the karst boundary influence range is 2D (D is the diameter of the tunnel), influence scope under the boundary of 3D, affecting range boundary is 1.2D; karst tunnel is located in the basement below, the safe thickness of the tunnel floor should be not less than 5m; the side of karst will lead to the stress concentration generated in the tunnel wall rock, and With the closer the stress concentration is greater. (4) when the karst tunnel in finite range, the boundary parameters of karst integration, a comprehensive study of its effects, and were named as the upper and lower shaft. Finally the simulation results show that the maximum impact range of shaft is 1.6d, the minimum range of influence -0.5d; minimum impact range is -3.1d. when the shaft bottom boundary than the basal surface of karst, karst tunnel loading has little effect on the substrate, but controlled by karst tunnel surrounding rock can not be ignored. (5) the results of numerical calculation based on data fitting using 1stOpt software, establish karst tunnel karst foundation considering the influence of boundary settlement the theoretical calculation method, and the calculation process of the interface and programs using graphical programming software Lab VIEW. According to the karst tunnel as an example, the use of the design of the basement settlement calculation procedures and examples in The calculation of the settlement of the channel base has been compared and analyzed to verify the reasonableness of the proposed method.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U451

【参考文献】