China News Service, Lhasa, October 20 (Ding Qing Binjiang Feibo) China Railway 11th Bureau revealed on the 20th that currently 63% of the Lalin section of the Sichuan-Tibet Railway has been laid and reached the Dagala Tunnel in Lang County, Nyingchi City. 17 kilometers, it is expected that the track laying in the tunnel will be completed on October 21.

It is worth mentioning that this is the first time railroad tracks have been laid in Nyingchi City’s history, ending the local history of no railroads.

  The new main line of the Lalin section of the Sichuan-Tibet Railway has a total length of 399.61 kilometers, passing through Gongga County, Nedong District, Lang County, and Milin County. It is the first electrified railway in Tibet with a design speed of 160 kilometers per hour and a bridge-tunnel ratio of 74. %.

The track laying machine pushes the rail row in the Dagala Tunnel in Lang County, Nyingchi City.

Photo by Li Chi

  According to the China Railway 11th Bureau, the Dagala Tunnel is 15.1 kilometers ballastless and 2.22 kilometers ballasted. It is a single-hole double-track, with a maximum altitude of 3120 meters.

Due to the special geographical location, the tunnel has 10.7 kilometers on a 10‰ ramp, which makes the construction difficult.

Faced with many unfavorable factors such as tight track laying schedule, multiple cross-working areas, and harsh weather, the project has made every effort to ensure the smooth track laying of the tunnel through technical means such as innovative construction techniques and transformation of mechanical equipment.

  "The communication equipment in the tunnel construction is not smooth, and the ventilation effect in the tunnel is not good, which brings huge pressure to the safe construction. In the face of the problem, after many on-site inspections, we decided to install a positioning label every 20 meters in the tunnel. A mini-signal station was installed." Guo Hongtao, the safety director of Lalin Railway Project of China Railway 11th Bureau, said that they also installed a signal receiving terminal on the locomotive. When the machine travels 20 meters in the tunnel, the data will be updated in real time. A voice prompt is issued to ensure the safety of construction traffic in the tunnel.

  In addition, the project also adopted the construction workers’ gas masks to replace the gas filter elements every three days, the wind and sand goggles were regularly cleaned by special personnel, and the construction adopted the “three shifts” method to reduce the working time of workers in the tunnel and ensure the track laying operation in the tunnel. Safe and orderly.

  It is reported that after the completion of the Dagala Tunnel, the track-laying mileage of the whole line will reach 258.25 kilometers, accounting for about 64.6% of the total task volume, laying a good foundation for the smooth completion of the Lalin section of the Sichuan-Tibet Railway in 2021.