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Though being built across a plateau where earthquakes frequently occur, the Qinghai-Tibet railway underway in western China should resist violent tremors thanks to preventive measures being taken, experts say.
Known as the "highest" railway of its kind worldwide, the 1100-km line is being built on the Qinghai-Tibet Plateau at an altitude of over 4000 meters, linking Golmud, a major city in Qinghai Province and Lhasa, capital of the Tibet Autonomous Region.
"Since last year we have mobilized many engineers and technicians to make a thorough geological survey in the seismic belt along the railway line," said Lu Ming, vice director of the seismic research center under the China Seismological Bureau.
"They have provided a detailed analysis of the location of major fault zones, the possibility of quakes, and magnitude of possible quakes," Lu said.
"Although violent quakes have occurred frequently on the Qinghai-Tibet Plateau, it does not rule out the feasibility of building a railway there," Lu said.
"We can reduce or avoid the quake threat as long as we detect accurately the geological conditions under the railway line and manage to go around the seismic belt or take other preventive measures," Lu added.
According to Zhao Shiyun, general engineer of the Qinghai-Tibet Railway Construction Headquarters, the railway would only vibrate slightly even in a violent earthquake, and the affected rails could be repaired and rapidly be back in use.
Li Jincheng, a senior engineer supervising the railway construction, said the line was designed to cross the seismic beltat right angles, which should reduce damage to the railway as much as possible.
"We try to avoid digging tunnels or building bridges when a railway crosses the seismic belt," said Li. "Instead, we use shallow foundations for rails, which may reduce quake damage to the minimum.
"When tunnels or bridges have to be built, we try to reduce their span and design their structure in a special way, which aimsto help them survive an earthquake measuring eight on the Richter Scale," Li said.
On November 14 last year, a serious earthquake measuring 8.1 on the Richter Scale jolted the Kunlun Pass on the Qinghai-Tibet Plateau, leaving a 400-km-long crack on the ground's surface.
"The earthquake had no remarkable impact on the railway," said Shi Jiaming, an official with a construction team working near the quake site.
"We saw the foundations of the rails shaking when the earthquake took place, but they did not break," Shi added.
As Tibet's first railway, the line from Golmud to Lhasa was started last June, and is scheduled to be completed by 2007. It isexpected to greatly promote the economic development of Tibet.
(People's Daily November 21, 2002)
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