复杂地层超大盾构始发技术及基坑受力研究

Study on Super-large Shield Launching in Complex Stratum and Foundation Excavation Stress Analysis

汕头苏埃通道采用15. 03m的超大直径泥水盾构施工,始发段地层条件复杂,含孤石和基岩凸起。介绍了复杂地层超大直径盾构始发施工技术,同时为了确保始发掘进推力下始发井基坑受力结构的强度和稳定性,建立基坑三维实体模型,考虑最不利工况,进行盾构掘进推力荷载作用下反力架支撑结构的受力和变形模拟,并进行施工中结构变形的实时监测,控制结构变形在合理范围内,有力保障了始发中的基坑结构安全。

The large diameter of 15.03 m slurry shield was used in Shantou Suai Channel Engineering with boulder and raised bedrock in shield launching formation.The construction technique of large diameter shield launching in the complex formation was introduced.Moreover to ensure the strength and stability of foundation excavation structure under initial excavating thrust,the three-dimensional entity model of foundation excavation was set up.Considering the most unfavorable condition,the stress and deformation simulation of supporting structure under shield tunnelling thrust was conducted.The structural deformation was monitored in real-time during construction so as to control structure deformation within a reasonable range,which ensured the safety of the foundation excavation structure strongly.