On January 25, 2026, with the last layer of rock and soil excavated, the Majie Tunnel of Tianlong Railway constructed by China Railway 14th Bureau was officially completed. As a first-class high-risk extra long tunnel with a total length of 12.4 kilometers, the project took more than 1200 days to construct. It not only overcame the extremely complex geological problems in the Qinba Mountain area, but also completed half a year ahead of the planned schedule. The breakthrough at this critical node has cleared the last obstacle for the full opening of the Tianlong Railway and laid a solid foundation for the improvement of the transportation network in southern Gansu.

The Tianlong Railway starts from Tianshui City in the north and ends in Longnan City in the south. The newly built main line has a total length of about 208 kilometers and a designed speed of 160 kilometers per hour. It is an important link in Gansu's transportation network. The Majie Tunnel is located in the Qinba Mountain area, with a total length of 12.4 kilometers. It is a first-class high-risk extra long tunnel and a key control project along the entire line.

The construction of Majie Tunnel is facing great challenges. The geological structure of the tunnel site area is complex, with developed fault zones. The tunnel passes through weak rock layers such as phyllite and slate, and the proportion of Grade IV and V surrounding rocks is 96%. The risk of collapse is high. The maximum burial depth of the tunnel is 1160 meters, while the minimum burial depth is only 31.6 meters. Risks such as high ground stress, large deformation, and eccentric pressure are intertwined. Meanwhile, due to the influence of fissure water, the maximum daily water inflow exceeds 14000 cubic meters, making construction extremely difficult.

For complex geology, the project team adopts advanced geological forecasting, intelligent monitoring platform, and 3D laser scanning technology to achieve dynamic warning. During construction, strict adherence to the principles of "weak blasting, short footage, strong support, early closure, pipeline ahead of schedule, and frequent measurement" is adopted, and the four step excavation method is used to control the deformation of surrounding rock. By setting up two inclined shafts and one horizontal tunnel, the "long tunnel short excavation" will be implemented, and six working faces will be simultaneously promoted during peak periods. Ultimately, the tunnel was completed six months ahead of schedule while ensuring safety. Keywords: construction news, railway transportation, Tianlong Railway

The Tianlong Railway is a key project in the national medium and long-term railway network planning, and also the first railway independently invested and constructed in Gansu Province. After completion, it will open up the southbound passage of Gansu, enhance the transportation capacity of the western land sea new passage, and promote the interconnection between the Silk Road Economic Belt and the Yangtze River Economic Belt. This railway is of great significance in improving the regional road network, filling the gaps in the road network, and optimizing the energy supply pattern, and will provide new impetus for the economic development of Gansu.Editor/Cheng Liting