某隧道施工技术数值模拟分析

发布时间：2019-05-16 23:29

【摘要】：进入21世纪以来,我国在铁路交通基础设施建设方面获得令人瞩目的成绩。尤其是近年来,其发展突飞猛进,高速铁路在我国已进入关键性的建设阶段,施工技术水平也有较大提高,铁路隧道的世界记录也不断被刷新。隧道工程施工技术也得到了快速的发展,其中隧道开挖技术势必成为隧道施工中的核心技术,也是研究隧道施工的热点。本文以某铁路隧道为工程背景,以弹塑性理论为基础,采用Midas-GTS软件进行数值模拟,分别分析了CD法、CRD法、微台阶法、二台阶五部法、三台阶三部法、三台阶七部法的施工过程,通过对比分析优选出合理的施工方法。主要得出了以下结论:(1)在二台阶五部开挖法施工当中,应当选择合理的台阶高度,充分发挥围岩自稳作用。(2)比较各种施工工法的受力特性,微台阶法、二台阶五部法表现较为均衡;三台阶七部法对围岩的稳定性有较大影响;三台阶三部法没有明显优势;CD法和CRD法在变形以及锚杆、钢拱架应力方面占据优势。(3)三台阶七部法开挖法是较成熟的短台阶法,适用于土质隧道施工,此方法非常利于对拱部初期支护、加强开挖未支护隧道的稳定性。CD法和CRD法适用于小型机械设备开挖,且中隔壁的拆除必须滞后于仰拱。(4)微台阶法、二台阶五部开挖法在受力方面较为均衡。从工程经济性角度评价,更有利于大型机械作业,更有利于隧道施工进度提高。对于本隧道,在保证隧道围岩稳定的前提下,选择微台阶、二台阶五部开挖法是适宜的。以上研究结果为浅埋破碎围岩段隧道施工提供了参考,为其应用于工程实践奠定了基础。
[Abstract]:Since the beginning of the 21 st century, China has made remarkable achievements in the construction of railway transportation infrastructure. Especially in recent years, with the rapid development of high-speed railway, high-speed railway has entered a critical stage of construction in China, the level of construction technology has also been greatly improved, and the world record of railway tunnel has been constantly updated. Tunnel construction technology has also been developed rapidly, in which tunnel excavation technology is bound to become the core technology in tunnel construction, and is also the focus of tunnel construction research. In this paper, taking a railway tunnel as the engineering background, based on the elastic-plastic theory, the numerical simulation is carried out by using Midas-GTS software, and the CD method, CRD method, micro-step method, two-step five-part method and three-step three-part method are analyzed respectively. The construction process of three-step and seven-part method is compared and analyzed, and the reasonable construction method is selected. The main conclusions are as follows: (1) in the construction of two-step and five-part excavation method, reasonable step height should be selected to give full play to the self-stability of surrounding rock. (2) the mechanical characteristics of various construction methods and the micro-step method should be compared. The performance of the two-step and five-part method is more balanced. The three-step and seven-part method has a great influence on the stability of surrounding rock, but the three-step and three-part method has no obvious advantages. CD method and CRD method have advantages in deformation, bolt and steel arch frame stress. (3) the three-step and seven-part method is a mature short-step method, which is suitable for the construction of soil tunnel, which is very beneficial to the initial support of arch. Strengthen the stability of excavated unsupported tunnel. CD method and CRD method are suitable for the excavation of small mechanical equipment, and the demolition next door must lag behind the inverted arch. (4) the micro-step method and the two-step and five-part excavation method are more balanced in terms of force. From the point of view of engineering economy, it is more beneficial to the operation of large machinery and to the improvement of tunnel construction progress. For the tunnel, under the premise of ensuring the stability of the surrounding rock of the tunnel, it is suitable to select the micro-step and the two-step and five-part excavation method. The above research results provide a reference for the tunnel construction of shallow buried broken surrounding rock section, and lay a foundation for its application in engineering practice.
【学位授予单位】：兰州理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U455.4

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