盾构长距离下穿运营地铁隧道施工技术研究

昆明某地铁区间盾构施工需长距离下穿既有运营地铁隧道，为确保安全，减少对既有隧道的影响，采取了地层加固、渣土改良、姿态控制等一系列技术措施。为进一步研究盾构下穿对既有地铁隧道的沉降规律，为后续施工提供指导，对下穿区段的既有地铁隧道进行了严密监测，获取了下穿施工时的沉降数据，对监测数据进行分析后，得出盾构长距离下穿既有运营隧道的沉降规律，取得了良好的施工效果。

Study on Construction Technology of Shield Tunneling Underneath Passing Operational Subway for a Long Distance

A shield machine of Kunming subway running tunnel needs to cross through the existing subway tunnel for a long distance. In order to ensure safety and reduce the impact on existing tunnels, a series of targeted technical measures such as ground reinforcement, soil improvement and attitude control are adopted. In order to grasp the rules of settlement and provide guidance for the subsequent construction, the existing subway tunnel of the section is carefully measured. The monitoring data is comprehensively analysed, then general settlement rules of the existing subway tunnel is summarized. Finally, good construction results have been achieved and it has important reference value for similar projects in the future.