The new Qinghai-Tibet Railway line the highest on earth will
endure the harsh conditions along the "Roof of the World" thanks to
new technology and constant monitoring.
Vice-Minister of Railways Sun Yongfu said: "It is a railway
we've made a whole lot of innovations and breakthroughs with. No
other country could build a railway on as high permafrost as
this."
With most of the new 1,110-kilometre track being laid at
altitudes above 4,000 meters, the line crosses 550 kilometers of
permafrost.
Based on preparatory work carried out over the past four
decades, Chinese engineers have used stone slabs to build
embankments that cool without breaking up, and thrust steel tubes
into the ground along some parts of the route, to transmit heat
from beneath the icy surface.
"We built bridges rather than causeways on extremely unstable
permafrost regions," Sun told China Daily.
"Construction on the permafrost regions appears to be of
excellent quality. During our trial runs this month, trains have
been rattling by at up to 100 kilometers an hour, much faster than
trains on railways in permafrost regions in other countries, which
can only travel at up to 70 kilometers an hour."
Despite the current stability of the recently completed track,
the Qinghai-Tibet Railway Corp, the railway's sole operator, will
have to work to ensure the line endures standing on the permafrost
in the long term, he said.
A long-term permafrost monitoring system has been installed to
check for changes in ground temperature and any deformities in the
rail bed, according to Zhang Luxin, a senior expert with the
Chinese Academy of Sciences.
Contingency measures have also been put in place to protect the
track from the worst hazard affecting the plateau global warming,
said Sun.
"We have taken account of the impact of global warming, but if
the temperature rises too much, extra solutions will have to be
found," he conceded.
Sun also said his ministry would spare no effort in addressing
the railway's environmental repercussions.
The ministry is determined to prove that the new line is
"harmonious with the ecology." For one thing, no waste will be
discharged along the road from the trains, according to Sun.
Lakes, plants and desertification along the route will be
monitored, as will animal populations, he said.
Asked about the hazard of natural disasters such as earthquakes,
which are frequent on the plateau, Sun said the route had been
designed to avoid regions with active seismic activity.
In the vulnerable regions that the track has to pass through,
constructors used rail beds rather than tunnels and bridges, and
retrofitted structures to minimize the effects of any possible
tremors, he said.
Sun said that from February, the Qinghai-Tibet Railway Corp has
been deploying staff along the new route. The company has employed
450 people for station and train services.
An additional 1,000 work on telecommunications and power supply
on the railway, he said.
"All the workers have undergone medical check-ups to make sure
they can react and adapt to high altitude conditions and effective
measures have been taken to improve working and living conditions
on the plateau," said Sun.
Monument
Sun, 65, who has directed the construction of a dozen railways
since 1962, said the Qinghai-Tibet Railway was the one that
impressed him most.
He said he was proud no workers died of altitude sickness during
construction, a testimony to the ministry's precaution
measures.
Sun revealed that the ministry is considering building a
commemorative structure on the Tanggula Mountain Pass, bearing the
inscription: "Altitude 5,072, the world's highest railway."
(China Daily June 26, 2006)