Guizhou's first shield machine, qianjin, started off smoothly

On September 19, as the new cutter plate of shield machine started to turn, the shield machine "qianjin" on the right line of the east section of guiyang rail transit line 3 was successfully started, which indicated that shield construction was officially adopted in guiyang rail transit construction.

The first phase of line 3 of guiyang rail transit officially started on December 30, 2018, starting from tongmuling station in huaxi and ending at luowan station in wudang district. The line is 43.03 kilometers long, with 29 stations and 30 sections. "Qianjin" is the first shield tunneling in guizhou province. It is specially designed for the characteristics of "high water pressure, hard rock strata and many karst caves" in guiyang. The first composite earth-pressure balanced shield machine in guiyang officially rolled off the production line on July 16, 2019. After more than 40 days of transportation and on-site assembly and debugging, a steel dragon will start a new journey in guiyang with the will of "underground elite".

Based on the comprehensive consideration of geological and hydrological conditions in guiyang area, "qian-jin" shield tunneling machine mainly designed the cutter disc, cutter, screw conveyer and other key parts, and added the advanced geological prediction system to detect and treat the underground karst. The shield machine in the section between normal college station and dongfeng town station starts from the large-mileage end of the open-cut section between normal college station and dongfeng town station.

The whole length of the area is 1109.283 meters. Above the ground of the area is the main road of the city, with a large traffic flow. The shield goes through chengxin machinery factory, guiyang-guangzhou high-speed railway and dongfeng town power supply station. The section mainly passes through moderately weathered limestone and moderately weathered mudstone layers, and the two sides of the road are mostly residential communities, which are difficult and risky to construct. In the early stage of the project, many difficulties such as pipeline relocation, large amount of immediate construction, large amount of karst cave treatment and high safety risk have been overcome.

In addition to shield construction in the division ~ east section, guiyang track no. 3 also USES shield construction in huaxi and other 18 sections of wudang district. 19 shield construction machines are planned to be put into operation. It is the first time for guiyang city to adopt shield construction method in urban rail transit construction, which will accelerate the construction progress and reduce the construction risk. Qian into "as the first of shield machine in guizhou, in guiyang area design is taken into account at the beginning of the" high water pressure, hard rock, karst cave ", such as geological conditions, hydrologic conditions, so the shield machine cutter disc and cutter, screw conveyor and other key parts of the specific design, at the same time increase the advance geological forecast system of the underground karst detection and processing.