金泉隧道Ⅳ级围岩级别细分及其稳定性控制研究

发布时间：2018-01-14 16:12

本文关键词：金泉隧道Ⅳ级围岩级别细分及其稳定性控制研究　出处：《重庆大学》2015年硕士论文　论文类型：学位论文

【摘要】：围岩稳定性是隧道工程建设中的重要研究内容。对围岩稳定性的准确认识,是岩体工程设计和制定施工方案、采取合理的工程处理措施以及保障施工安全的基础。然而,由于地质条件以及地下工程本身的复杂性、不可预见性以及勘察方法和手段的有限性,在其设计阶段取得详细地质、围岩参数和设计荷载参数等数据极其困难,设计阶段的岩体分级往往与施工现场岩体的级别不符。因此,在隧道施工过程中,地质工作者必须随隧道施工过程,根据现场的地质条件、超前地质预报结果和监控量测分析,对设计阶段的围岩分级和设计参数进行修证,对施工方案进行调整。本文结合金泉隧道工程实例进行研究,研究内容和结论如下:①通过对现场地质条件的观察,发现金泉隧道洞身的进口段与出口段围岩岩性和岩层厚度有明显的差异,在施工工程中所表现出稳定性也有差别。故而通过现场观察和现场TGP试验,实验室岩石物理力学实验等方法对其进行围岩级别细分,将洞身段围岩分成Ⅳ1和Ⅳ2两个亚级。②针对级别细分后的围岩,调整原设计的施工方法和初期支护方案,设计另外两种方案进行研究。③应用Flac3D对不同级别围岩采用不同方案进行模拟,通过分析应力状态、位移变化和塑性区情况来研究其稳定性情况,研究结果表明:1)Ⅳ1级围岩在原设计方案全断面开挖一次进尺3m时具有一定的自稳能力,采用原设计支护方案能有效限制围岩变形。2)Ⅳ2级围岩在全断面一次开挖3m时,自稳能力较差,在施作初期支护之前就常发生坍塌;当开挖进尺减小到2m时,坍塌现象有效地得到缓解,只有小范围落石;当采用台阶法时,稳定性进一步得到加强。④现场进行监控量测,分析位移变化规律,根据监控量测结果的反馈,隧道采取调整后开挖方式、支护方案后整体稳定性较好。
[Abstract]:The stability of the surrounding rock is an important research content in the construction of tunnel engineering. To accurately understand the stability of the surrounding rock, rock engineering design and construction scheme, take reasonable engineering measures and guarantee the safety of construction of the foundation. However, because of the complexity of geological conditions and underground engineering itself, LIMITED unpredictability and investigation methods and means the detailed geology in the stage of design, extremely difficult rock and design load parameter data, rock mass classification design stage and construction site often does not match the rock level. Therefore, in the tunnel construction process, geological workers must follow the process of tunnel construction, according to the geological conditions of the site, measurement of geological prediction results and monitoring, the surrounding rock classification and design parameters for the design phase of the permit, to adjust the construction plan. The alloy spring Tunnel Engineering Case studies, research contents and conclusions are as follows: through the observation of field geological conditions, found that the Kimcheon tunnel entrance section and the exit section of the surrounding rock lithology and strata thickness have significant differences, in the construction project performance stability are different. So through on-site observation and TGP testing laboratory, physical and mechanical rock experiment was done on the rock level subdivision, will be divided into 1 rock cave figure IV and IV 2 and two sub classes. The rock level segments after the adjustment, the original design and construction method of the initial support scheme of two kinds of scheme design. The other application of Flac3D of different levels with different surrounding rock for simulating the stress state through the analysis, the displacement and the plastic zone to study its stability. The results show that: 1) IV 1 Rock in a full section excavation footage of the original design Has a certain self stability of 3M, the original supproting design can effectively restrict the deformation of the surrounding rock.2) IV 2 Rock in the full face excavation 3M, poor stability, as the initial support before the collapse often occur in Shi; when the excavation footage is reduced to 2m when the collapse phenomenon eased effectively, only a small range of rockfall; when using the step method, the stability is strengthened. The field monitoring measurement, analysis of the change regularity of displacement feedback, according to the monitoring results of the tunnel excavation method, take after adjustment, the supporting scheme after the whole stability is good.

【学位授予单位】：重庆大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U452.12

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