超大直径盾构隧道管片上浮原因与对策分析

An Analysis of Causes and Countermeasures of Segment Floating of Super Large Diameter Shield Tunnels

超大直径盾构隧道管片的抗浮问题是其普及化的瓶颈.系统总结和分析了管片上浮的原因和机理:包括地质条件、盾构工法特性及施工参数、盾构姿态、覆土厚度、管片接头、施工扰动、注浆工艺和浆液特性等.并就控制超大直径盾构隧道管片上浮提出了具体措施,以期能对超大断面的水底隧道、地铁区间隧道的浅覆土盾构施工起到借鉴作用.

Because of its anti-floating problem,super large diameter shield tunnel segment finds itself difficult to gain popularization.The analysis suggests that performances and mechanism of segment floating are closely related to geological condition,characteristics and construction parameters of shield construction,shield attitude,covering depth,joints of segment,construction disturbance,grouting technology,grout characteristics,and the like.Moreover,some concrete countermeasures are proposed to control the uplift of the super lager diameter shield tunnel segments,with a view to yielding some insights into construction of shallow covering shield in underwater tunnels and metro tunnels with super large diameters.