Hard rock tunnel boring machine begins drilling for key water diversion project

By Tan Maolin.

A large hard rock boring machine began drilling a key section of China’s on-going national water diversion project in Yichang on January 5.

Nicknamed "Jianghan Ping’an,” the machine has a diameter of 11.93 meters, making it the largest of its kind in China. Approximately 180 meters long and weighing around 3,550 tons, it represents a feat of Chinese engineering.

Photo by Xiao Yijiu.
 

Equipped with two shields and advanced technologies such as proactive geological detection, machine jamming alerts and cutter status monitoring systems, the machine can efficiently drill through complex geological layers, such as extremely hard rock and rock bursts and withstand high external water pressure.

Photo by Xiao Yijiu.
 

The boring machine was deployed to drill a 16.6 km underground water diversion tunnel. This tunnel belongs to a larger project linking up the Yangtze River's Three Gorges Reservoir and the Danjiangkou Reservoir at the border of Hubei and Henan provinces. The new project will transport water through tunnels and leverage the Han River, covering a total length of 194.8 kilometers.

Prior to the deployment of Jianghan Ping’an, excavation of the main tunnel had reached 3.8 kilometers, while that of branch tunnels exceeded 16 kilometers.