变质软岩隧道大变形稳定性评价及防治分级研究  

Study on Stability Evaluation and Prevention Classification of Large Deformation in Metamorphic Soft Rock Tunnel

作　　者：吴大勇 WU Dayong(Citic Construction Co.,Ltd.,Beijing 100027,China)

机构地区：[1]中信建设有限责任公司,北京100027

出　　处：《粉煤灰综合利用》2025年第1期82-88,共7页Fly Ash Comprehensive Utilization

摘　　要：为有效评价变质软岩隧道大变形的稳定性,并合理划分其防治等级,以上军楞隧道为工程背景,在开展其大变形特征分析基础上,先利用尖点突变分析评价隧道大变形段的稳定性,再通过累计变形判据和变形速率判据开展隧道大变形的防治分级研究。结果表明:上军楞隧道在大变形分析断面的变形监测成果中,其水平收敛的变形范围为142.03~219.28 mm,拱顶沉降的变形范围为153.20~251.62 mm,均明显大于变形控制值,具显著的变形特征。在大变形段的稳定性评价结果中,相应监测断面条件下水平收敛的Δ值均大于拱顶沉降的Δ值,即在隧道大变形段,拱顶沉降具相对更大的失稳、塌方风险,且局部位置处的Δ值已小于0,局部失稳风险较大。在隧道大变形段的防治分级研究结果中,两类判据的分级结果存在一定差异,按不利原则,建议研究的大变形断面均按Ⅳ级进行防治。因此,在上军楞隧道施工过程中,一旦发生大变形,其稳定性一般相对偏弱,且具较高的防治等级,建议严格按照分析方法开展施工预警,避免造成不必要损失,为其后续施工提供了一定的技术指导。In order to effectively evaluate the stability of large deformation in metamorphic soft rock tunnels and reasonably classify their prevention and control levels,the Junling Tunnel is taken as the engineering background.Based on the analysis of its large deformation characteristics,the stability of the large deformation section of the tunnel is first evaluated using sharp point mutation analysis.Then,the prevention and control classification of large deformation in the tunnel is studied through cumulative deformation criteria and deformation rate criteria.The analysis results show that in the deformation monitoring results of the large deformation analysis section of Shangjunleng Tunnel,the deformation range of horizontal convergence is 142.03~219.28 mm,and the deformation range of arch crown settlement is 153.20~251.62 mm,both of which are significantly greater than the deformation control values and have significant deformation characteristics.In the stability evaluation results of the large deformation section,the Δ values of horizontal convergence under the corresponding monitoring section conditions are all greater than the Δ value of arch crown settlement.That is to say,in the large deformation section of the tunnel,the arch crown settlement has a relatively greater risk of instability and collapse,and the Δ value at local positions is less than 0,indicating a higher risk of local instability.In the research on the classification of prevention and control of large deformation sections in tunnels,there are certain differences in the classification results of the two criteria.According to the principle of disadvantage,it is recommended that the large deformation sections studied be prevented and controlled according to level IV.Therefore,in the construction process of Shangjunleng Tunnel,once large deformation occurs,its stability is generally relatively weak and has a high level of prevention and control.It is recommended to strictly follow the analysis method to carry out construction warning,avoid unnece

关 键 词：隧道 大变形 稳定性 防治分级 

分 类 号：TU735[建筑科学—建筑技术科学]