On August 13, a good news came from the construction site of Yunnan Da-Lin Railway. After 1572 days of hard work by the builders, the key control project of the entire line-Dabang No. 5 Tunnel was successfully completed, laying the foundation for the completion and operation of the entire line as scheduled.

  Dabang Fifth Tunnel is located in Yunxian County, Yunnan Province, with a total length of 6316 meters. It is a Class I risk tunnel and is one of the key control projects on the entire line. The rock mass in the tunnel is mainly soft rock such as sericite schist and carbonaceous schist. Affected by multi-stage earthquakes and tectonic stress, the rock mass is broken, with low strength and poor resistance to disintegration, and it is easy to soften when exposed to water. There is soft rock during construction. Construction risks such as large deformation and collapse are extremely easy to occur. The maximum deformation is more than 1 meter, and the construction is extremely difficult.

  In view of the complex geological conditions of the tunnel, the Dianxi Railway Construction Headquarters of China Railway Kunming Bureau Group organized design, construction, supervision and other participating units, and through measures such as optimizing construction organization and adjusting technology and construction methods, a set of practical construction plans was summarized The highest monthly construction progress of the Dabang Five Weak Surrounding Rock Tunnel reached 99 meters, laying the foundation for the smooth completion of the tunnel on schedule.

  The Dali Railway departs from Dali Station, passes through Weishan County and Nanjian County in Dali Prefecture, crosses the Lancang River and then passes through Yun County to Linxiang District of Lincang City. With a total length of 202 kilometers, it is a national railway class I single-track electrified railway. Once completed and opened to traffic, it will play a positive role in the interconnection between China and neighboring countries.

  Currently, the work of the Dalin Railway is progressing as planned. The tunnel was 99.6% completed, the bridge was 99.3% completed, and 84.5% of the total initial design investment was completed on the entire line. (Wang Peng Wang Yixiang Hao Yafan)

Editor in charge: 【Luo Pan】