In April 18th, the domestic first railway large diameter soil pressure /TBM double die boring machine was accepted in Changsha. The equipment was developed by China iron construction heavy industry group Co., Ltd., with complete independent intellectual property rights, and will be used in the intercity rail transit line of the Pearl River Delta.
The total section tunnel boring machine products in China are divided into two types: shield machine and TBM (rock tunnel boring machine). The shield machine mainly consists of soil pressure balance, mud water balance and so on. It is applied to soft soil and composite strata that can not be self stabilized on the excavation surface, such as urban subway tunnel, river tunnel, and so on. TBM is mainly applied to hard rock with stable formation. Geological Tunnel Engineering, such as mountain ridge tunnel, diversion tunnel, etc.
In short, the single mode shield machine has low driving efficiency in the extreme hard rock formation, "eat" hard rock, TBM "hard" is not "soft", and can not be drifting in the complex formation. The previous off-line dual mode tunnelling machine, although it has two functional models of earth pressure balance shield machine and hard rock TBM, carries out one mode conversion for up to 2 months, which affects the whole project period.
Project head, Chen Qingbin, director of the earth pressure shield Research Institute of the research and Design Institute of iron construction heavy work boring machine, introduced that the first earth pressure and the TBM two functional modes can coexist online double mode tunnelling machine, not only can "apply both hard and soft", but only need 72 hours to complete the earth pressure balance shield machine model and hard rock TBM mode. Mutual conversion provides powerful equipment support for tunnel rapid, efficient and reliable construction.
It is reported that the diameter of the equipment is 9.15 meters, the length of the whole machine is 115 meters, the total weight is about 1350 tons, and the installed power is 5700 kilowatts. The intercity railway tunnel of Guangfo ring line has many difficulties, such as large section of excavation, complex hydrogeological conditions, high compressive strength crossing the stratum rock and about 6000 meters long distance driving, so the single mode shield machine can not meet the complex construction requirements.
