隧道全长粘结锚杆锚固参数优化及无损检测技术研究

发布时间：2019-01-28 07:58

【摘要】：由于地质环境的复杂以及人们对锚杆作用机理的研究不够深入,缺少行之有效的、合理的计算模型,对锚固参数估算不准确等因素的限制,使锚杆支护设计存在一定的局限性;另一方面,由于锚杆工程结构具有隐蔽性和施工工序相对较为复杂以及施工队伍操作水平层次不齐等特点,这些可能影响到整个岩土工程结构的质量和长期稳定安全,控制锚杆施工质量也存在一定难度。基于此,锚杆机理研究,锚固参数优化和锚杆质量检测水平仍然需要进一步研究和尝试。本文在前人研究成果的基础上,结合广东省南粤交通揭(阳)惠(来)高速公路建设项目中小北山1#隧道工程实际,基于对隧道围岩稳定性的研究及全长粘结式砂浆锚杆的支护机理的研究,引入均匀设计试验方法,建立隧道开挖衬砌锚杆支护有限差分数值模型。分别以锚杆长度L,直径D,布设间距Sx,布设排距Sr为影响因素,参考规范建议选取6个水平,以拱顶位移、周边收敛值、围岩最大主应力和锚杆最大轴力为因变量,采用向后逐步回归法对数值模拟结果进行回归分析,得到不同锚固参数对于锚杆支护效果的影响,并优选出最佳的锚杆支护方案,为隧道锚杆设计提供有意义的参考。同时基于应力波的理论基础,研究锚杆锚固质量检测的技术方法和应力波在一维锚杆中传播时波动方程,探讨了应力波在锚杆中的传播规律,根据锚杆无损检测的内容,探讨应力波法的判断方法和依据。结合现场实际工程应用,使用应力波法对锚杆施工质量作出评价,指导施工。
[Abstract]:Because of the complexity of geological environment and the lack of deep research on the mechanism of bolt action, the lack of effective and reasonable calculation model and the limitation of inaccurate estimation of anchor parameters, there are some limitations in bolt support design. On the other hand, because of its concealment, relatively complex construction procedure and uneven operation level of the construction team, these may affect the quality and long-term stability and safety of the whole geotechnical engineering structure. It is also difficult to control the construction quality of anchor rod. Based on this, the study of anchor mechanism, the optimization of anchoring parameters and the level of anchor quality inspection still need further study and attempt. On the basis of the previous research results, this paper combines the reality of the small Beishan 1# Tunnel Project in Guangdong Province's Nanzhou-Guangdong Jiaotong (Yang) Hui (Lai) Expressway Construction Project. Based on the study of the stability of surrounding rock of tunnel and the supporting mechanism of full-length bonded mortar bolt, the finite difference numerical model of tunnel excavation lining bolting is established by introducing the uniform design test method. In this paper, the length of anchor rod L, diameter D, arrangement distance Sr of Sx, spacing are taken as the influencing factors, and the six levels are suggested to be selected according to the specification. The dependent variables are arch displacement, peripheral convergence value, maximum principal stress of surrounding rock and maximum axial force of anchor rod. The regression analysis of the numerical simulation results is carried out by using the backward stepwise regression method. The influence of different anchoring parameters on the bolting effect is obtained, and the optimal bolting scheme is selected, which provides a meaningful reference for the tunnel bolt design. At the same time, based on the theoretical basis of stress wave, the technical method of anchor anchoring quality detection and wave equation of stress wave propagating in one-dimensional anchor are studied, and the propagation law of stress wave in anchor rod is discussed, according to the content of non-destructive testing of anchor rod, The judgment method and basis of stress wave method are discussed. The stress wave method is used to evaluate the construction quality of anchor rod and guide the construction.
【学位授予单位】：华中科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.7;U456.3

【参考文献】