First: the first mud shield started the construction of sea crossing section 8 line.

This morning, the slurry shield tunneling started smoothly from Dayang Station of Qingdao Metro Line 8 to the east of Qingdao North Station, which is the first slurry shield tunneling across the sea since the construction of Qingdao Metro.

 It is understood that the cross-sea section is the key control project of Metro Line 8, with tight construction period, heavy tasks and high technical content. The rapid and smooth start of the slurry shield tunnel is of vital importance to speed up the subway passage from Qingdao North Station of China Unicom Line 8 to Qingdao Jiaodong International Airport.

Dayang-Qingdao North Railway Station has a total length of 7.8 km. There are 3 air wells and 1 inclined shaft in the section. The section is divided into two working areas on the East and West sides. The western side is constructed by inclined shaft mining method, and the eastern side is constructed by shield method. The Eastern cross-sea section of Daqing section is the throat of the whole subway line 8, with a total length of about 3.87 km, and the shield section of land section (3 # to 2 # wind shaft) is about 0.98 km, using an earth pressure balanced shield machine; the shield section of sea area section (2 # wind shaft to the receiving end of the seabed) is about 2.89km, using two mud water balance. Shield machine, a total of 3 shield machine construction. This is the beginning of the sea area. The maximum slope is 28 per thousand, and the 2 air shaft is the bottom of the sea. This project includes 1 segments of shield interval, 1 segments of open cut interval, 2 ventilation shaft and 6 connection channels. After the completion of the tunnel, close transfer can be achieved at Qingdao north station and Metro Line 3 and line 1.

 Line 8 is about 60 kilometers in length, starting from JiaoZhou North Railway Station, and finally to 54 square, with multiple subway lines. Line 8 is the main artery of Qingdao which connects the new airport, the northern urban area and the main urban area. The maximum speed of the underground section is 120 km/h. It is less than an hour from the May 4th Square to Jiaodong Airport. It is very important for the rapid development of the northern city and the implementation of the urban development strategy of "three zones, one axis, three bays, three cities, and a group type" Great significance.

At present, the cumulative entry rate of line 8 is 89.9%, and the operating rate is 86.1%. The main concrete structure of the airport station has been capped and the shield tunneling section has been connected by two lines. There are 1 viaduct station to achieve the main concrete structure of the top; 4 underground excavation stations have entered the main excavation stage of earth and rock, 1 station in the shaft (inclined shaft) excavation stage; 10 open excavation stations in addition to Cangkou Station, Yanjiashan Station has not yet entered the site, Hongdao Railway Station (non-co-construction section), 5 stations are in the main node. During the construction stage, the remaining stations are in the excavation stage. Eight sections of the middle-north glue section, glue-glue section, glue-glue section, glue-glue section, Dahong section, Guanke section, Keda section, cross-sea section on the west side of Daqing section and mining method section in Shanwu section have entered the main line of excavation; the glue-glue section and glue-glue section in the elevated section are carrying out the construction of the lower and upper structures of the elevated section. The left line of the North rubber section of the shield section has been completed.

The geological conditions of Line 8 are complex, the construction is difficult, the line crosses rivers, beaches and sea areas, the topography and landforms are diverse, and the geological conditions are more complex and changeable; the types of engineering structures and construction methods used are comprehensive and diverse, including roadbed, bridges and tunnels, open-cut and underground excavation, mining and mechanical excavation, and the whole line construction machine. The degree of mechanization is high, about 28.6 km, accounting for 47% of the total length of the line; the external coordination workload is large, and the line has repeatedly crossed the railway, national highway, provincial highway, highway, bridge, densely populated areas and so on. The section of the ocean station passes through the Jiaozhou Bay area from the ocean station to the Qingdao north station, and the sea area is about 5.43km.

 Qingdao Metro Group will, in accordance with the requirements of the Municipal Party Committee and the Municipal Government, speed up the construction of the subway project on the premise of ensuring the quality and safety of the project, give priority to the construction of the subway at key nodes such as Jiaodong International Airport, and constantly improve the subway network to better meet the travel needs of citizens.