盾构隧道联络通道钢管片快速开口施工技术研究

Rapid Opening Technology of Steel Pipe Sheet for Connecting Gallery of Shield Tunnel

为研究不同开口型式下盾构隧道联络通道处管片的受力及变形特征,选出较为安全、快速的开口型式,依托广州市轨道交通18号线琶洲西区站—冼村站区间1#联络通道,通过数值模拟、现场实测等方法,开展盾构隧道联络通道钢管片快速开口施工技术研究。结果表明:1)盾构隧道联络通道处采用钢管片施工可减少对围岩及隧道管片的扰动;2)提出的4片钢管片开口型式可保障管片受力,避免结构失稳,开口后形成的回字形承载结构保留了完整的受力体系,可缓解联络通道开口处的应力集中;3)联络通道施工时采用“4片钢管片+混凝土管片”通缝拼装的支护方式与临时支撑相互配合,能够保障结构的承载能力。

To study the stress and deformation characteristics of the segments at the connecting gallery of shield tunnels under different opening types of steel pipe,and select a safer and faster opening method,a case study is conducted on#1 connecting gallery of Pazhou west station-Xiancun station in Guangzhou,China.The numerical simulation and field measurement methods are carried out to study the rapid opening technology of steel pipe sheet of shield tunnel.The results show the following:(1)The use of steel pipe sheets at the connecting gallery of shield tunnel can reduce the disturbance to the surrounding rock and the tunnel segments.(2)The opening type with four steel pipe sheets is proposed to ensure the force of the segments and avoid structural instability.The formed homocentric squares loadbearing structure retains a complete force system,which can alleviate the stress concentration at the opening of the connection gallery.(3)The connection gallery construction adopts the support method of four steel sheets and concrete pipe support,and temporary support can guarantee the bearing capacity of the structure.