【作者】 乔卖青；

【导师】 张志强；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2012， 硕士

【摘要】 本文基于交通部科研项目“大相岭隧道岩爆及大变形控制技术研究”,采用理论研究、监控量测与离散元数值模拟等方法,对大相岭隧道穿越高地应力断层破碎带的大变形发生机理进行了研究,在此基础上提出了高地应力断层破碎带围岩量变形预测的方法,并编制了相关的预测程序。另外本文还分析了大相岭隧道穿越断层破碎带的支护的安全性,并且进一步优化了支护结构。本文研究的内容主要从以下几个方面展开：(1)结合国内外对于软弱围岩大变形研究的现状和断层破碎带围岩的变形特点,总结出围岩大变形发生的机理及常见的大变形的判据,进而选取出本文所使用的断层破碎带围岩大变形的判据。(2)本文应用GA遗传算法来训练BP人工神经网络,充分发挥了GA算法的全局搜索优化的能力及BP神经网络算法的局部搜索优化的能力,综合二者的长处编制了大相岭隧道高地应力断层破碎带围岩变形量的预测程序GA—BP神经网络遗传算法,并且与工程实测值进行对比,论证了其的实用性。(3)由于高地应力断层破碎带的地质条件极其复杂,围岩极其破碎,为了有效的模拟断层破碎带围岩的工程力学特性,本文使用了三维离散元软件3DEC来进行数值模拟计算,分析了大相隧道的断层破碎带围岩的变形、受力特征,引入了剪切滑移区的概念来进一步分析围岩发生大变形的机理。(4)本文针对大相岭隧道支护设计方面存在的问题,从锚杆的长度、纵向间距、隧道的断面形状以及支护施作的时机等方面展开可支护的优化工作,为今后的高地应力断层破碎带围岩的支护设计提供了有效的参考。更多还原

【Abstract】 By taking of the Ministry of Transportation western transportation construction technology project " Study on Daxiangling Tunnel Rock Blasting and Large Deformation Control Technology", the site monitoring measurement, theoretical analysis and three-dimensional numerical simulation were carried out to investigate the high ground stress fault fracture zone deformation mechanism in the key controlling project of Yaxi highway—Daxiangling deep and extra-long tunnel.In this paper, the method of fault fracture zone deformation prediction has been proposed, and the forecasting process has been programmed. In addition, the security of Daxiangling Tunnel support through the fault fracture zone was analyzed and the supporting structure was further optimized.The main research results was following:(1) Combination of weak surrounding rock deformation to study the status and fault broken with the surrounding rock deformation characteristics, summed up the mechanism of surrounding rock mass deformation and large deformation criterion, and then select the large deformation criterion of this article.(2) In this paper, Training the BP neural network by GA genetic algorithm, and give full play to the ability of local search optimization of the global search optimization of the GA algorithm and BP neural network algorithm, the integrated superiorities of both the preparation of Daxiangling tunnel’s high ground stress fault fracture zone rock mass deformation prediction program GA-BP neural network genetic algorithm and contrast to demonstrate its practicality of the project measured.(3) Due to the fault fracture zone of high field stress is extremely complex geological conditions, the surrounding rock is extremely broken, in order to effectively simulate faults with the surrounding rock engineering mechanical properties, using the three dimensional discrete element software3DEC numerical simulation, analysising the mass deformation characteristics of Daxiangling tunnel and stress characteristics, For further analysis of surrounding rock major deformation mechanism the paper recommended of the concept of shear slip zone.(4) Large relative to the tunnel support design problems in the Bolt length, vertical spacing optimization, the cross sectional shape of the tunnel as well as support facilities for the timing to provides a valid reference point for the future high ground stress fault fracture zone rock mass support designing.更多还原