October 1，Lhasa-Xigaze Airport Section of Ya'an-Yecheng National Expressway（La-Ri Expressway for short）The longest tunnel, Padang Mountain Tunnel, runs through the whole line.，It marks another significant progress in the construction of the La-Ri Expressway.。

Padang Mountain Tunnel is the second phase project of La-Ri Expressway.（Middle section）Key and difficult control projects，Constructed by China Railway 21 Bureau。The average elevation of Padang Mountain Tunnel is 3760 meters.，The left line is 4587 meters long.、The total length of the right line is 4573 meters.，It is the longest tunnel on the La-Ri Expressway.，It passes through the lower part of the slope on the right bank of the Yarlung Zangbo River.，The construction site is located in the high mountain and gorge landform area in the south-central Qinghai-Tibet Plateau.，Most of the rock mass in the area is broken.，The main geological problems encountered during the construction include the collapse and rockfall of the slope at the entrance and exit of the tunnel.、Tunnel bias、Valley unloading、Geothermal, etc，At the same time，There are also disaster risks such as debris flow at the entrance of the tunnel，The construction is difficult.。

The construction of Padang Mountain Tunnel is carried out by simultaneous excavation at both ends of the entrance and exit.。In the course of construction，Affected by adverse geological conditions，The builder encountered shallow burial.、Water gushing、Bias failure, etc“Obstacles”。Transportation Department of Tibet Autonomous Region、Leaders of the District Key Highway Construction Project Management Center have visited the construction site for many times.，La-Ri Expressway Construction Headquarters and China Railway 21 Bureau, the contractor of Padang Mountain Tunnel，With“Build a satisfactory traffic for the people”As one's own duty，Face difficulties with a strong sense of mission and responsibility，Strengthen construction organization in the whole process、Quality Control and Safety Management，In the construction of the fracture zone，Adopt geological radar、Advanced technology and process for mutual confirmation of electromagnetic transient and advanced borehole，Accurately grasp the geological surrounding rock conditions in front of the tunnel face，So that that blas can be reasonably arranged，And that monitor of the support deformation is effectively strengthened.。In the process of overcoming difficulties，The project headquarters and construction units are based on modern management concepts.、Advanced technology、Construction technology and excellent style，It ensures the smooth penetration of the Padang Mountain Tunnel.。

It is reported that，The second phase of the La-Ri Expressway is being constructed in an all-round way（Middle section）Total length 91.108 kilometers，The ratio of bridge to tunnel is as high as 71.64%，The completion of the Padang Mountain Tunnel laid a solid foundation for the completion of the La-Ri Expressway on schedule.。During the Mid-Autumn Festival and National Day，All participating units stick to their posts and work overtime，Grasp the precious construction season and make every effort to promote the progress of each bid section。

The La-Ri Expressway is an important part of the opening of the Tibet Autonomous Region to South Asia.，Yeah, too“The Belt and Road”The initiative is oriented to Nepal and other neighboring countries.。At the same time，Lhasa-Xigaze Section of National Highway 318，It is also one of the busiest highways in the Tibet Autonomous Region.，After the opening of the La-Ri Expressway, it will become an important passageway from Lhasa to the western part of Tibet.，It will further optimize the regional road network structure.，Improve road transport capacity and driving safety，It has also improved the national comprehensive transport corridor.，To promote“A circle of two wings”Urban construction，Making positive contributions to the improvement of the three-hour economic circle with Lhasa as the core。

Source | Tibet Transportation Department