Recently, the first domestic smallest diameter open tunnel tunnel boring machine independently developed by China Railway Construction Corporation and Iron & Steel Construction Heavy Industries Group Co., Ltd. has created a new record for tunnel excavation in the water distribution project in northern Hubei. Meters, the highest single-day footage of 43.914 meters, the highest monthly footage of 864.37 meters into the good performance.
Baolin tunnel construction site
The TBM has a diameter of 4 meters, a length of 290 meters and a weight of about 750 tons with a total installed power of 2,400 kilowatts and commenced trial excavation on April 5. Due to volume limitations, the cutterhead can only be designed with 24 hobs installed and each rolled The carrying capacity of the knife is limited.Research and development team and on-site service personnel of CCTZR have made many demonstrations and researches and made reasonable adjustments to the parameters of excavation to make the equipment make good achievements in construction operations and the equipment intact rate reaches more than 97%.
The Baoling Tunnel is 13.84 km in length, of which TBM has a total length of 10.6 km and a maximum depth of 649 m. The TBM is mainly composed of gneisses and hard rock with a saturation compressive strength of 60-137 MPa, and there are many more Article fault rupture zone, while the middle without maintenance branch hole, construction difficulty and geological conditions is rare.
In response to these geological and construction challenges, IRC R & D designers have optimized the limited space of TBM to a maximum and customized drill rig systems, steel arch systems and sprayed concrete systems to make the equipment safer, faster, Environmental protection.