浅谈泥水盾构卵石层加压进舱技术

Technology of Slurry Shield Pebble Bed Pressurized into the Tank

摘要: 在盾构工程中，穿越透水、易坍塌和不稳定的卵石层,一直是施工的重难点。瓯江盾构隧道全长834.5 m，主要穿越地层为中砂层、卵石层、安玢岩。其中，卵石层长度超过300 m，最大卵石粒径达到450 mm，60%卵石粒径超过150 mm，卵石占比超过90%以上。刀盘破碎筋无法进行大粒径卵石破碎，随着掘进长度增加，大粒径卵石逐步累积，使刀盘扭矩增大进而被卡，需要加压进舱作业进行刀盘舱内卵石清理。瓯江盾构工程通过完善加压进舱技术，确保了300多米卵石层掘进的顺利完工，为今后泥水盾构卵石层加压进舱提供了技术借鉴及参考。

Abstract: In the shield project, crossing through the permeable, collapsing and unstable pebble layers has been the critical and difficult point of construction. Oujiang shield tunnel was 834.5 m long, it was mainly crossing through the formation of medium sand bed, pebble bed and andesitic porphyrite. Among them, the pebble bed was more than 300 meters long, the largest pebble grain size was 450 mm, 60% of pebble grain size was more than 150 mm, its proportion was more than 90%. For the tool pan break ribs large grain size pebble was hard to be broken, with the increase of the excavation length, the large grain size pebble was cumulated step by step, the tool pan torque increases and stuck tool occurs, pressurizing the pebble into the tank was needed for tool pan cleaning in the tank. In Oujiang Shield Project, by the improvement of technology of pressurizing into the tank, it ensures the smooth excavation of 300 long pebble beds. It provides technical reference for pebble bed pressurizing into the tank for the slurry shield projects.