海底隧道施工期塌方机理及处置方法研究

发布时间：2018-07-09 18:11

  本文选题：海底隧道 + 塌方原因　； 参考：《湖北工业大学》2017年硕士论文

【摘要】：在海底隧道施工中,塌方是一种常见的事故,隧道塌方的影响因素很多,治理比较困难,塌方事故一旦发生,不仅延误工期,提高工程费用,损坏施工机械,甚至造成人员伤亡。本课题以某电厂位于海底的取排水隧道工程为案例,全面分析了隧道塌方事故发生的原因,提出海底隧道塌方的处置方案,并运用数值仿真模拟的方法,对隧道塌方的处置过程进行了模拟对支护结构的受力特性进行了分析,对处置方案的安全性进行了评价,并对其进行了优化分析,,对以后类似隧道塌方的治理有实际的指导和借鉴意义。通过分析得出了以下主要结论:(1)海底隧道局部坍塌的影响因素一般有地质条件,地下水,设计、施工以及管理因素等几个方面。在这些因素中,不良地质条件属于引起隧道坍塌的一个非常重要的原因,地下水则是隧道塌方的第二位的影响因素。当然隧道建设过程中隧道设计、隧道施工和管理中的一些因素也同样不能忽略,这些都是引起隧道塌方的相关因素。(2)针对某电厂取排水隧道工程塌方实例,可以得到海底隧道洞口段地质条件一般较差,围岩极为破碎、承载能力很差,围岩级别一般为Ⅳ或Ⅴ级,若发生塌方,其基本处置步骤为:塌体控制,塌体表面处理,塌体坡脚加固,塌体内部处理,拱顶上部塌腔处理,隧洞开挖支护,塌方体二次开挖支护,监控测量。(3)对某电厂取排水隧道工程塌方进行应力场、位移场的数值模拟得出:上下台阶开挖会导致应力释放现象,位移也会增大,隧道围岩的最大应力主要集中在上下台阶交接处,施工时应注意此区域的施工质量,及时施工二衬可以有效的增加隧道围岩的稳定性。(4)如果发生海底隧道塌方需按照“先治水,后加固;防扩大,再处理”这一处置原则进行处置,按照工程实际状况选择适合的开挖方法及支护方式,施工中坚持信息化指导,不断提高施工的管理水平,施工中始终要遵循开挖能量最小原理,避免对围岩稳定性造成影响,这是优化海底隧道塌方处置方法的最基本途径。
[Abstract]:In the construction of subsea tunnel, collapse is a kind of common accident. There are many influencing factors of tunnel collapse, so it is difficult to deal with it. Once the collapse accident occurs, it will not only delay the construction period, but also increase the project cost and damage the construction machinery. It even caused casualties. Taking the drainage tunnel project of a power plant located at the bottom of the sea as an example, the cause of tunnel collapse accident is comprehensively analyzed, and the disposal scheme of subsea tunnel collapse is put forward, and the method of numerical simulation is used. The process of disposal of tunnel collapse is simulated. The mechanical characteristics of supporting structure are analyzed, and the safety of disposal scheme is evaluated. The optimization analysis is carried out, which has practical guidance and reference significance for similar tunnel collapse treatment in the future. The main conclusions are as follows: (1) the influencing factors of subsea tunnel local collapse are generally geological conditions, groundwater, design, construction and management factors. Among these factors, poor geological conditions belong to a very important cause of tunnel collapse, and groundwater is the second factor affecting tunnel collapse. Of course, some factors in tunnel design, tunnel construction and management can not be ignored in the process of tunnel construction. These factors are related factors that cause tunnel collapse. (2) A case study of tunnel collapse in a power plant drainage tunnel. It can be obtained that the geological conditions of the tunnel entrance section are generally poor, the surrounding rock is extremely broken, the bearing capacity is very poor, and the surrounding rock grade is generally 鈪，

本文编号：2110244