富水软土地区盾构掘进关键参数统计分析研究

    Statistical analysis of key parameters for shield tunneling in water-rich soft soil areas

    • 摘要: 针对天津地铁某线盾构工程中推力、土仓压力、推进速度等关键掘进参数及沉降现场实测进行统计分析,探究盾构掘进参数的变化规律及其对地表沉降的影响。通过数据统计以及各参数之间的相关性研究发现:土仓压力与覆土厚度呈正相关,盾构推进过程中稳定在(0.9~1.1)倍的隧道埋深处侧向静止土压力;推力波动于(1.8~2.4)倍土仓压力在开挖面的作用力。地表沉降监测显示,先行线在盾构到达和工后固结沉降均大于后行线;横断面沉降对隧道净距敏感,净距小于2.5倍隧道直径(15 m)时,沉降槽的形态由“W”变为“V”。研究还通过Spearman热力图及基于随机森林的特征重要性分析方法筛选出影响地表沉降的关键盾构参数,土仓压力、同步注浆量、出土方量对沉降的影响较大,在施工中应严格控制。研究结果为盾构施工参数优化和地表沉降控制提供了科学依据,对类似工程具有重要的参考价值,有助于提高地铁建设的安全性和效率。

       

      Abstract: This study statistically analyzes on-site measurements of key tunneling parameters (including thrust, soil chamber pressure, and advance speed) and surface settlement in a shield tunneling project on a Tianjin Metro line, aiming to investigate the variation patterns of shield tunneling parameters and their influence on surface settlement. Through statistical analysis and correlation studies of the parameters, the following findings are obtained: soil chamber pressure exhibits a positive correlation with overburden thickness; during shield advancement, it stabilizes at 0.9~1.1 times the lateral static earth pressure at the tunnel burial depth. Thrust fluctuates within the range of 1.8~2.4 times the force exerted by soil chamber pressure on the excavation face. Surface settlement monitoring indicates that both the arrival settlement and post-construction consolidation settlement of the leading tunnel are greater than those of the trailing tunnel. Cross-sectional settlement is sensitive to the tunnel net distance: when the net distance is less than 2.5 times the tunnel diameter (15 m), the settlement trough morphology transitions from a "W-shape" to a "V-shape". This study further identifies key shield parameters affecting surface settlement using Spearman correlation heatmaps and random forest-based feature importance analysis. Results show that soil chamber pressure, synchronous grouting volume, and muck discharge volume have a significant impact on settlement and thus require strict control during construction. The findings provide a scientific basis for optimizing shield tunneling parameters and controlling surface settlement, offering valuable references for similar projects and contributing to enhanced safety and efficiency in metro construction.

       

    /

    返回文章
    返回