News Center

Qingdao metro tunnel construction uses special cement impermeable and waterproof


On the afternoon of May 8, Fan Yanxiang, chief engineer of Qingdao Project Department of China Railway Bureau 19, introduced to Qingdao media reporters the first phase of the subway line to achieve the first section and station through the connection. Located in Nanjing Road, it is one of the sections with the largest traffic volume and human flow in the urban area, as well as one of the most difficult sections for construction. Fan Yanxiang explained that considering the station's location is a bustling urban area, with large traffic flow, dense underground pipelines and high surface settlement control standards, the main structure and air duct of the station on Jiangxi Road are all excavated with a large excavation surface and a depth of about 20 meters.

On the afternoon of May 8, Fan Yanxiang, chief engineer of Qingdao Project Department of China Railway Bureau 19, introduced to Qingdao media reporters the first phase of the subway line to achieve the first section and station through the connection. Located in Nanjing Road, it is one of the sections with the largest traffic volume and human flow in the urban area, as well as one of the most difficult sections for construction. Fan Yanxiang explained that considering the station's location is a bustling urban area, with large traffic flow, dense underground pipelines and high surface settlement control standards, the main structure and air duct of the station on Jiangxi Road are all excavated with a large excavation surface and a depth of about 20 meters.

Wearing a hard hat and plastic rain boots, the reporter followed subway workers down layers of iron stairs that only allowed one person to pass through to the underground construction site of the Jiangxi Road station, 25 meters below the ground. At the scene, the reporter saw a machine with roughly the same shape as the tunnel stopped inside the dug tunnel. The equipment, named "lining trolley", is mainly used to pour concrete into the tunnel walls, according to the staff.

In addition, at the construction site of the station, there are three workers climbing up a ladder to the upper wall busy. "They're treating it with impervious water." Fan Yanxiang told reporters that the station site is located under Nanjing Road, the top of the station is only 10 meters away from the road, and the vault is in strongly weathered granite, the upper part of the artificial filled earth, coarse gravel sand layer, the formation is weak and strong permeability. In addition, the section through which the station passes is rich in groundwater, and often seepage occurs, which has a certain impact on the construction. Reporters saw the scene from time to time there are big drops of water dripping down from above, there are a lot of water on the ground. "To prevent seepage, we use special cement against them." Fan Yanxiang told reporters that it is to the place where the water seepage pouring sulfur aluminate cement. It acts like super glue and quickly "fuses" with the soil at the seepage site. After adopting this method, the water seepage is obviously reduced, and the effect of waterproof and water stop is better.

At present, 22 stations of Metro Line 3 are fully under construction, 18 section shafts are all under construction, control center, rolling stock and other projects will be started in the near future. Up to now, a total of 1,090 meters of upper steps have been excavated at underground stations of the first phase of the subway project, 1.218,400 million cubic meters of earth and rock excavation have been completed at open-cut stations and sections, 87,800 cubic meters of main concrete has been poured, and 7,429 meters of tunnel excavation has been completed at underground sections.

 

Copyright © 2022 Beijing NovElite Co.,Ltd. All Rights Reserved