On January 21, after more than three years of hard work, Keshiketeng Tunnel, the longest tunnel in the electrification reconstruction project of Jining Tongliao Railway, was completed by China Railway Electrification Engineering Group.
Keshiketeng Tunnel is located in Keshiketeng Banner, Chifeng City, Inner Mongolia Autonomous Region, with a total length of 10.691 kilometers and a maximum buried depth of 267 meters. It is a single-hole double-track tunnel with three inclined shafts. The tunnel is famous for "complex geological conditions, frequent changes in surrounding rock, development of underground water system, frequent water gushing and mud gushing". It passes through nine fault fracture zones, with poor rock integrity and stability, and nearly 46% of the surrounding rock of Grade IV and V.
Keshiketeng Tunnel is located at the intersection of Yanshan Mountain and Yinshan Mountain. The surface is dry, but the groundwater is extremely abundant. Under normal circumstances, the water inflow of the main tunnel is about 60,000 cubic meters per day, sometimes the maximum water inflow is more than 170,000 cubic meters per day, and the total drainage is 34.647 million cubic meters, which is equivalent to the water storage capacity of 2.4 times of West Lake in Hangzhou.
