Xiamen Metro Line 3 construction to create a new record
At a depth of 60 meters below sea level in the eastern waters of Xiamen Island, the shield machine on the right line of the cross-sea section of the Metro Line 3(Liuwudian) is undergoing the final construction of the disposal operation. The giant completed its excavation mission and was dismantled in the tunnel at 7:18 on the 20th, creating a new domestic record of 30 days to complete the "Dissolution of the Shield Machine in the Tunnel Tunnel".
As one of the important investment projects in the city's "double hundred billion yuan" work, subway and supporting development are advancing rapidly and becoming a new growth pole that supports the rapid development of the city. The total length of the Xiamen Main Island to Xiang 'an Cross-Harbour Pass Wuyuan Bay Station-Liuwudian Station is about 4.9 kilometers. Due to Geological changes, the shield machine set off from Liuwudian station and dug 1.4 kilometers to the island. It was necessary to stop work and change to the mining method. The shield machine can only dig forward and can not retreat. In order to make room for the construction of the ore mountain method that has been taken over, the shield machine disintegrates the shell in situ, and then disassembles all parts from the tunnel. In addition to being located at a depth of 60 meters below sea level, the idea of creating a shaft directly from the top to hang out parts can not be realized. The construction personnel can only dismantle the shield machine one by one and use a 5-meter-long battery car to make a trip to the original road.
Don't underestimate the work of dismantling and transporting Shields. The shield weighs more than 800 tons and is 107 meters long. The blade diameter is 7.02 meters, which is even higher than the two floors. The number of parts is more than 14,000. In order to provide sufficient construction time for subsequent construction, the dismantling operation time is only one month. Therefore, it has never been implemented in China to achieve the safety of the tunnel demolition, sealed packing and smooth delivery of difficulties.
To this end, the construction unit carried out a special design. "Considering the location, it is easy to see the phenomenon of water and sand inflow. The construction personnel use curved steel plates to weld the seal pipe plate and shield shell clearance, shield shell micro-expansion cement closure, and air intake. Double wind tube smoke discharge and other measures, The parts of the shield machine were successfully shipped out. "The safety and quality director of the Xiamen Cross-Harbour Pass project, Zhaobaojun, told reporters that more than 50 % of these dismantled parts can be reused.
In the end, the construction unit successfully avoided the occurrence of various risks and successfully completed the "Dissolution of the Shield Machine in the tunnel tunnel" operation within a month.
From the track group, it was learned that 26 stations across the Metro Line 3 have now completed the construction of 1 station main body, and 22 stations have carried out enclosure, earthwork and main structure construction; Fifteen intervals carry out encirclement and main structure construction, and the interval is dug into 19.5 %.