富水地层盾构始发洞门密封关键技术研究

Research on the Key Technology of Cave Door Sealing of the Shield Machine Departing in the Water⁃Rich Strata

盾构始发时,洞门密封失效易导致安全事故。针对高富水砂层,基于现有洞门密封系统,研发一套刚柔并济复合式盾构密封装置。该装置由柔性密封结构和刚性密封结构组合而成,柔性密封结构由改进后的折页板、橡胶帘布组成,刚性密封结构由伸缩式钢板、磁性钢片、收紧装置等部件组成。采用柔性及刚性密封构件进行多次密封,解决了在涌水涌砂量较大复杂地质条件下洞门密封难题,保证密封效果,提高了盾构始发的安全性。该工艺措施已成功应用于各种复杂环境下高富水地层的洞门密封,大幅提高了盾构始发阶段的安全性和施工效率。

In the process of shield machine departing,the safety accidents are likely to occur if the tunnel door sealing fails.Based on the existing tunnel door sealing system,a rigid and flexible composite shield sealing device was developed for the high water⁃rich sand layer.The sealing device consists of a flexible sealing structure and a rigid sealing structure.The flexible sealing structure is composed of an improved folding plate and a rubber cord.The rigid sealing structure is composed of retractable steel plate,magnetic steel sheet,tightening device and other components.Through flexible and rigid sealing components,multiple sealing was carried out to solve the problem of cave door sealing in the complex geological conditions with high water⁃rich sand layer,ensuring the sealing effect and improving the safety of shield departure.This construction method has been successfully applied to seal the tunnel door in high water rich strata in various complex environments,which greatly improves the safety and construction efficiency of the shield starting stage.