Chongqing-Kunming railway sees key tunnel cut through

The Luorongzhuang tunnel of the Chongqing-Kunming railway

After some 940 days of hard work by the builders at China Railway No.4 Engineering Group, the Luorongzhuang tunnel of the Chongqing-Kunming railway was holed through on August 1.

Located in central Yunnan’s Songming county, the single-hole and double-line tunnel has a length of 5,260 meters, and the complex geological conditions have made the tunnel a key project on the railway.

 

Interior of the Luorongzhuang tunnel 

In holing through the tunnel, the Chinese railway builders used special engineering measures, such as controlled blasting, mechanical excavation and high-precision large pipe shed, to improve work efficiency.

The Chongqing-Kunming railway is part of the Beijing-Kunming line, and the Yunnan section extends 388.6 kilometers. With a design speed of 350 kilometers per hour, it is expected to cut the Chongqing-Kunming trip from 5 hours to 2 hours upon its operation.

 

Interior of the Luorongzhuang tunnel 

Source: Yunnan Daily; Trans-editing by Wang Shixue