软土地层地铁盾构下穿车站咽喉区施工技术

Construction Technology of Metro Shield Tunnel Undercrossing the Throat Area of Station in Soft Soil Stratum

上海地铁15号线盾构隧道下穿上海南站咽喉区。通过方案比选、下穿工程影响数值模拟,形成了综合考虑施工条件和对车站咽喉区影响的线路方案。根据咽喉区列车通过能力,制定了列车限速和运营调整方案。制定地层斜向注浆加固方案,采用高性能全新土压平衡盾构机和新型相对质量密度大的单液浆减少车站咽喉区地表变形,并采用自动化连续监测和实时反馈的信息化施工方法。该技术措施将下穿咽喉区盾构施工中地表沉降控制在4.5 mm以下,可供类似工程参考。

The shield tunnel of Shanghai Metro Line No.15 under-crosses the throat area of Shanghai south railway station.Through the comparison and selection of schemes and the numerical simulation of the influence of undercrossing engineering,a line scheme was formed to balance the construction conditions and reduce the impact on the throat area of the station.According to the passing capacity of the train in the throat area,the train speed limit and operation adjustment scheme were formulated.The inclined grouting reinforcement scheme was drawn up,a new highperformance earth pressure balance shield machine and a new type of single liquid slurry with high relative mass density were used to reduce the ground surface deformation in the throat area of the station,and the information construction method of automatic continuous monitoring and real-time feedback was adopted.This technical measure can control the ground settlement below 4.5 mm during the shield construction undercrossing the throat area,which can be used as a reference for similar projects.