软土地区浅埋大直径盾构隧道管片上浮规律及预测： 以上海机场联络线工程为例

为探究软土地区浅埋大直径盾构隧道管片上浮规律及其影响因素，本文依托上海机场联络线浅埋大直径盾构隧道工程案例，基于实测数据分析了盾构姿态变化对管片上浮的影响，揭示了管片上浮量与施工参数之间的相关关系，提出了考虑多因素的管片上浮非线性预测方法。研究结果表明，管片上浮主要可分为脱出盾尾前初始偏差及变形、快速上浮（盾尾5环）、缓慢上浮（盾尾5-15环）和沉降等4个阶段；盾构姿态、管片姿态与超挖是影响管片上浮特性的重要因素；管片上浮量与平均推力、盾构仰角、平均推进速度呈正相关，与上下盾尾间隙差呈负相关，采用多元非线性拟合方式可以综合考虑多因素较好地预测管片上浮量。本文相关研究可为大直径盾构隧道施工过程中上浮预测与控制提供参考。

Regularity and prediction of segment floating of shallow buried large diameter shield tunnel in soft soil area: A case study on Shanghai airport contact line

In order to explore segment uplifting pattern and influencing factors of large-diameter shield tunnel in soft soil area, based on the measured data of project of shallow buried large-diameter tunnel of Shanghai airport contact line, the influence of shield attitude change on segment uplifting was analyzed. The correlation between segment uplifting and tunnelling status was revealed. And a nonlinear prediction method for segment uplifting considering multiple factors is proposed. The process of segment uplifting can be divided into four stages: initial deviation and deformation before exiting the shield tail, rapid uplifting (5 rings from the shield tail), slow uplifting (5-15 rings from the shield tail) and settlement. Segment uplifting is greatly affected by shield attitude, segment attitude and overcutting. The uplifting of the segment is positively correlated with the average thrust, shield elevation and average propulsion speed, while negatively correlated with the gap difference between lower and upper shield tails. The nonlinear fitting method can predict tunnel uplifting well taking multiple factors into consideration. The research can provide reference for prediction and control of uplifting of shallow large-diameter shield tunnel.