China is building a rail tunnel, deep below the Great Wall of China
China is constructing a 12 kilometre long high-speed train tunnel through a section of the Great Wall to connect Zhangjiakou city, which is due to co-host the 2022 Winter Olympics along with Beijing.
Chinese Engineers designed the tunnel to be constructed from 4 metres to 432 metres in depth below the Badaling section of the Great Wall to cater for trains travelling up to 350 km per hour.
When completed in 2019 the journey time will be cut from plus 3 hours down to about one hour. A station will also be built in the centre of the tunnel some 102 metres under Badaling Great Wall.
To ensure that the Great Wall is not damaged in the process “precision micro-blasting” technology will be employed, which has a velocity of 0.2 cm per second and able to make the tremor weaker than traditional firepower blasts that have a velocity of 5 cm per second.
The Great Wall of China
The Great Wall stretches over 21,000 km and built from the third century BC to the Ming Dynasty (1368-1644). Over a four million tourists visit the Great Wall every year.
The Great Wall has deteriorated over time from the effects of nature, about 30% a 6,200-km section of the wall built in the Ming Dynasty has disappeared.