地下车库改造对邻近运营地铁隧道的影响

The Impact of the Underground Garage Improvements on the Adjacent Operational Metro Tunnel

摘要: 邻近运营地铁隧道的新建或改造地下工程，除了要注意基坑安全，区间隧道的变形也是需要关注的重点。本文以杭州市某邻近地铁隧道的地下车库改造工程为例，采用“分坑施工”的设计方案，结合施工期间对地铁隧道的全过程监测，研究地下车库改造对邻近运营区间隧道的影响。本文施工经验表明：分坑施工的设计方案有利于控制基坑变形和邻近区间隧道的变形；已有地下室的清障方案需考虑施工进度，应避免因清障而耽误基坑支护结构施工；地下车库改造期间邻近区间隧道会随着土体向基坑侧水平位移，并伴随有道床沉降和水平收敛，并进一步引发隧道漏水和裂缝，因此对基坑和区间隧道的实时监测尤为重要。

Abstract: For new or rebuilt underground projects close to operational metro tunnels, the deformation of the tunnel is also a key concern in addition to the safety of the foundation pit. This paper takes an un-derground garage renovation project near the underground tunnel in Hangzhou as an example, adopts a “split-pit construction” design scheme, combines the whole process monitoring of the un-derground tunnel during construction, and studies the impact of the underground garage renova-tion on the adjacent operational tunnel. The construction experience in this paper shows that the “split-pit” design solution facilitates controlling deformations in the pit and in the adjacent tunnel; The clearance plan for existing basements needs to take into account the construction schedule, and the construction of foundation support structures should avoid being delayed by clearance; During the renovation of the underground garage, the adjacent tunnel will move horizontally with the soil to the foundation side, accompanied with settlement and horizontal convergence, and will further cause tunnel leakage and cracks, so real-time monitoring of the foundation and tunnel is particularly important.