特拉维夫富水砂层盾构短套筒始发技术研究

Study on shield launching technology of short sheath in the water rich sand stratum at Tel Aviv

以色列特拉维夫轨道交通红线盾构始发施工区段处于富水砂层,传统始发方法已不适用。通过研制钢制短套筒装置,使盾构顺利完成始发。短套筒始发技术解决了端头加固难的问题,避免了使用由橡胶帘布和扇形压板组成的密封性不稳定的传统洞门密封方法。盾构始发前在洞口安装导向环及密封环,密封环内安装橡胶密封及砂浆袋;始发时先在橡胶密封之间填充油脂,而后向砂浆袋内注入砂浆,分别阻塞盾构外壳与开挖面及盾构外壳与管片之间的空隙,防止涌水。结果表明,短套筒始发技术具有经济效益高、安全可靠、施工速度快等优点。

The Red Line shield launching construction section at Tel Aviv rail transit in Israel is located in water rich sand stratum, so the traditional launching method is not applicable. Through R&D of the short steel sheath device, the shield was successfully launched. The short sheath launching technology solves the problems of difficult end reinforcement and avoids the traditional method of portal sealing, which is composed of rubber curtain and fan-shaped pressing plate. Before the departure of shield, guide ring and sealing ring are installed at the tunnel portal, and rubber seal and mortar bag shall be installed in the sealing ring. During the launching, grease is filled between rubber seals, and then mortar is injected into the mortar bag to block the gap between shield shell and excavation face, shield shell and segment respectively, so as to prevent water gush. The results show that the launching technology of short sheath has the advantages of high cost effectiveness, safety and reliability, and fast construction advance.