富水含砂软土地层轨道交通盾构选型及施工效果

苏州轨道交通2号线盾构隧道主要穿越黏土、粉细砂土层,地下水位较高,选择合适的盾构机形式是实现洞通的关键。通过参考国外选型经验及国内盾构选型状况,根据2号线的工程地质和水文地质条件,结合其工程特点,按照"安全性、适应性、经济性、环保性"的原则,对加泥式土压平衡盾构和泥水平衡式盾构这两类型盾构进行比选,确定2号线区间隧道使用土压平衡盾构,最终成功穿越运营城际铁路风险较大的工程,未发生重大安全事故,并按计划顺利实现洞通节点目标,相关经验可供类似工程参考。

Selection and Construction Effect of Rail Transit Shield in Soft Soil Layer with Rich Water and Sand

Shield selection is very important for building the shield tunnel for Suzhou Rail Transit Line 2 because a large part of the tunnel has to pass through the areas with the clay and fine sand soil with high groundwater level.The paper introduces the shield selection and the construction effect of the rail transit tunnels in the soft soil layer of rich water and sand.The shield selection for the project of Suzhou Rail Transit refers to the domestic and foreign experiences of shield selection,takes into account the engineering geological conditions and the characteristics and follows the principles of "being safe,economic and friendly to the environment." By comparing the two types of shield tunnel,that is,the earth pressure balance shield (EPB) and slurry balanced shield,the EPB shield is adopted for Line 2.With the adopting of the EPB shield,the tunnel ultimately succeeded in crossing the in-operation intercity railway with high construction risks,without causing major accidents,and the node target is reached with throughing hole as planned.