China’s new railway tunnel squeezed by tectonic crush in Tibetan snow mountain
- In less than a month, the tunnel in Yunnan was reduced from a diameter of 12 metres to less than 3 metres as a result of shifting tectonic plates
- Engineers working on the project are now looking for solutions to the unprecendented challenge
The power of nature has created an unprecedented problem for engineers building a railway in southwestern China after shifting tectonic plates squeezed sections of a tunnel.
Some completed sections of the 9km (5.6-mile) Haba Snow Mountain Tunnel were hit by a crushing force caused by the collision of the Indian and Eurasian plates, the team said.
In less than a month, the tunnel in the Deqen Tibetan autonomous prefecture in Yunnan was squeezed from a diameter of 12 metres to less than 3 metres – barely enough for a car to pass – the project engineers told Science and Technology Daily in a report published on Wednesday.
Instrument readings suggested the rocks around the tunnel had come under pressure as great as 30 megapascals, equal to the combined weight of 75 elephants standing on a single foot.
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Major tunnel completed for Yunnan-Tibet railway in southwest China
The rocks were mostly formed by lava, making them too soft to bear the burden.