公路软岩隧道小型拱形塌方腔体稳定性及处治措施研究-岩土工程专业论文.docxVIP

万方数据 万方数据 摘 要 塌方是隧道施工中最常见的灾害现象之一。目前，隧道塌方问题的研究主要集中于 原因分析及处治措施，对塌方腔体周边围岩稳定性尚未有系统的分析。一般情况下，隧 道塌方处治主要针对大、中型塌方事故，对小型塌方受关注较少，但工程实践中，大部 分的大、中型塌方都是小型塌方没能得到及时治理而造成的；同时隧道塌方事故中小型 塌方所占的比例较大。因此，开展小型塌方腔体周边围岩稳定性与处治措施研究对保障 施工安全具有着重要的指导性意义。本文基于软弱围岩隧道塌方的特点，采用统计分析、 理论分析与数值模拟相结合的方法，对自重应力场作用下公路隧道塌方腔体周边围岩稳 定性及处治措施进行深入的研究。论文主要工作如下： 1.对无支护条件下与有支护条件下隧道塌方事故进行了分类统计，统计分析的内容 主要有塌方腔体形状、位置、时间节点、原因以及塌方处治方法。 2.基于统计分析，对无支护条件下隧道拱形塌方进行了数值模拟，分析了塌方腔体 周边围岩的位移场、应力场以及围岩塑性区。 3.基于统计分析，对有支护条件下隧道拱形塌方进行了数值模拟，分析了塌方腔体 周边围岩的位移场、应力场、围岩塑性区以及支护结构受力特征。 4.在无支护条件下与有支护条件下隧道拱形塌方数值模拟分析结果的基础上，分别 依据塌方腔体周边围岩塑性区位置或应力松弛最严重部位，对两种条件下的隧道塌方提 出了处治方案，进行了数值模拟分析，得到了不同施工阶段下隧道各个部位的位移变化 规律、围岩塑性区变化情况、以及支护结构受力特征，并进行了对比分析，对处治方案 的处治效果作出评价。 关键词：隧道工程、塌方、稳定性、处治措施、统计分析、数值模拟、对比分析 I ABSTRACT As a tunnel collapse in one of the most common disaster phenomena . At present , the issue of tunnel collapse focused on the Causes and Treatment Measures for stability analysis collapse of the cavity surrounding rock yet systematic analysis , Under normal circumstances, the tunnel collapse Treatment mainly for large and medium-sized cave accidents, landslides affected less attention to small , but it works in practice , in many cases large and medium-sized by a small landslide landslides are not able to get timely treatment caused; and tunnel collapse accident larger proportion of a small landslide .Therefore , to carry out small-scale collapse of the cavity surrounding rock stability and Treatment Measures for safe construction has important guiding significance. Based on the characteristics of weak rock tunnel collapse , using statistical analysis, theoretical analysis and numerical simulation method, the stress field under its own weight highway tunnel collapse of the cavity surrounding rock stability and treatment measures in-depth study . The main contents are as follows: Under the conditions and there is no support in tunnel collapse accident statistics of supporting conditions , statistical analysis of the contents of the main cave shape , location , ti