On October 4, 2021, China Railway 22nd Bureau Group completed the construction node of the China-Laos railway ballastless track.

The Jingzhai Tunnel on the China-Laos Railway has a total length of 9.5 kilometers, a single-track tunnel with a speed of 160 kilometers per hour, and the last "fortress" to be conquered on the entire line. After the completion and opening, the train only needs 4 minutes to pass, but the builders of China Railway 22nd Bureau Group have been here for more than 1,700 days and nights. In response to multiple adverse factors such as narrow work surface, complex procedures, high temperature in the cave, difficulty in supply, etc., China Railway 22nd Bureau Group has inverted the construction period, clearly defined the division of labor, and carefully organized it to complete the construction of 168 meters of ballastless track in a single day, which is a domestic breakthrough. Construction records. Editor/Sang Xiaomei