World's First Ultra-high Voltage (UHV) River-crossing Integrated Tunnel is Fully Excavated on August 21, 2018

The world's first ultra-high voltage (UHV) river-crossing integrated tunnel is fully excavated on August 21, 2018. [Photo/sasac.gov.cn]

World's first ultra-high voltage (UHV) river-crossing integrated tunnel is fully excavated on August 21, 2018

The GIL (gas insulated transmission line) integrated tunnel connecting Suzhou and Nantong, part of the 1000 kV Huainan-Nanjing-Shanghai UHV AC transmission engineering, was completely excavated on August 21, 2018.

The project, invested and constructed by the State Grid Corporation of China and China Railway Construction Corporation Limited respectively, is an ultra-long-distance GIL innovation project with the highest voltage level, the largest transmission capacity and the highest technical level in the world.

This is the first time in the world GIL technology was used in UHV transmission. It provides a new solution for the construction of transmission channels facing conditions such as rivers, seas and densely populated areas. 

World's longest heavy haul railway tunnel completed on August 21, 2018

The Yaoshan Tunnel of the western Inner Mongolia-to-central China railway, the world's longest heavy haul railway, was completed on August 21, 2018.

Designed and contracted by China Railway Construction Corporation Limited, the double-tube single-lane tunnel is 22.77 kilometers in length.

It is the longest tunnel of the railway and was constructed under complicated geological and hydrological conditions.

Going through 21 fault fracture zones at a maximum burial depth of 500 meters, the tunnel project was very difficult to control.

The railway has evolved into a strategic energy passage for China's North-to-South Coal Diversion Project.

It is significant for the development of coal mines in Inner Mongolia and the Ningxia Hui autonomous regions, as well as Shaanxi and Gansu provinces, and guarantees energy supply to Middle China and economic and social development in affected areas.

(Executive editor: Hao Wen)