Featured Research

from universities, journals, and other organizations

New Railroad Across Tibet Conquers Permafrost Using Crushed Rocks

Date:
December 27, 2004
Source:
University Of Colorado At Boulder
Summary:
Engineers constructing a new railroad across the vast, high-altitude Tibetan Plateau are using a surprisingly simple idea to fortify shifting frozen soils affected by climate warming, according to a University of Colorado at Boulder permafrost expert.

Engineers constructing a new railroad across the vast, high-altitude Tibetan Plateau are using a surprisingly simple idea to fortify shifting frozen soils affected by climate warming, according to a University of Colorado at Boulder permafrost expert.

Related Articles


"The Qinghai-Xizang railroad is the most ambitious construction project in a permafrost region since the Trans-Alaska Pipeline," said CU-Boulder and National Snow and Ice Data Center researcher Tingjun Zhang. Zhang is working closely on the project with scientists at the Cold and Arid Regions Environmental and Engineering Research Institute in Lanzhou, China.

"This is the first time engineers are primarily using crushed rock to insulate and fortify a structure against permafrost," he said.

Zhang will discuss the railroad project and the effects of widespread warming and thawing of frozen soils across the northern hemisphere at a press briefing in San Francisco Dec. 13 as part of the American Geophysical Union's annual meeting. He will lead a panel of permafrost and climate experts from universities in the United States, Canada and the United Kingdom.

"If current observations are indicative of long-term trends, we can anticipate major changes in permafrost conditions during the next century," Zhang said. "Permafrost is thawing in many regions, and it is significantly influencing landscapes and ecosystems."

One example is the Tibetan plateau, where the 695-mile Qinghai-Xizang railroad is due to be completed in 2007. More than 600 miles of track will be at altitudes of at least 13,000 feet above sea level, and 340 miles of track will lie across permafrost. Half of the permafrost area the tracks will cross is categorized as "high-temperature permafrost," Zhang said, meaning that the frozen soil is only 1 or 2 degrees Celsius below freezing.

"The permafrost presents a challenge, because the climate of the area is predicted to become warmer during the next 50 to 100 years, and construction and train activity on the surface can also create heat and cause melting," Zhang said. "The shifting soils can ruin railroad tracks, roads and buildings.

"In order to keep the track straight and the railroad foundation stable, engineers are using crushed rock to both insulate and cool the permafrost," he said.

Using on-site experiments and mathematical heat transfer modeling, engineers determined that a 2- to 3-foot layer of loose, medium sized rocks minimizes heat intake to the soil under railroad embankments during warmer months and promotes heat loss in winter.

"The rock layer is so effective that it actually helps create a net cooling effect over time," Zhang said. One experiment detailed in Zhang's presentation for the AGU meeting showed the permafrost under a railroad embankment was actually colder after a year of crushed rock insulation.

Though crushed rock permafrost insulation was first investigated as early as the 1960s, this is the first time a large-scale project is using the technique as one of its primary solutions, according to Zhang. The railroad also is using other means to cool and protect the soil, including shading, insulation and "passive heat pumps" comprised of piping that conducts heat from the ground and circulates cold air.

"Crushed rock is the most cost-effective method," Zhang said. "It's mainly labor costs."

Zhang is a researcher at the National Snow and Ice Data Center and the Cooperative Institute for Research in Environmental Sciences, both of which are affiliated with CU-Boulder. He earned bachelor's and master's degrees in physical geography from Lanzhou University in China. He holds master's and doctoral degrees in geophysics from the University of Alaska, Fairbanks.

Zhang is currently the principal investigator on five frozen-ground research projects around the world, with funding from the National Science Foundation, NASA, the International Arctic Research Center at the University of Alaska-Fairbanks and the National Institute for Global Environmental Change at the U.S. Department of Energy.


Story Source:

The above story is based on materials provided by University Of Colorado At Boulder. Note: Materials may be edited for content and length.


Cite This Page:

University Of Colorado At Boulder. "New Railroad Across Tibet Conquers Permafrost Using Crushed Rocks." ScienceDaily. ScienceDaily, 27 December 2004. <www.sciencedaily.com/releases/2004/12/041219152823.htm>.
University Of Colorado At Boulder. (2004, December 27). New Railroad Across Tibet Conquers Permafrost Using Crushed Rocks. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2004/12/041219152823.htm
University Of Colorado At Boulder. "New Railroad Across Tibet Conquers Permafrost Using Crushed Rocks." ScienceDaily. www.sciencedaily.com/releases/2004/12/041219152823.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Will New A350 Help Airbus Fly?

Will New A350 Help Airbus Fly?

Reuters - Business Video Online (Dec. 22, 2014) Qatar Airways takes first delivery of Airbus' new A350 passenger jet. As Joel Flynn reports it's the planemaker's response to the Boeing 787 Dreamliner and the culmination of eight years of development. Video provided by Reuters
Powered by NewsLook.com
Man Parachutes Off Lawn Chair Airlifted By Helium Balloons

Man Parachutes Off Lawn Chair Airlifted By Helium Balloons

Buzz60 (Dec. 22, 2014) A BASE jumper rides a lawn chair, a shotgun, and a giant bunch of helium balloons into the sky in what seems like a country version of the movie 'Up." Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Touch-Free Smart Phone Empowers Mobility-Impaired

Touch-Free Smart Phone Empowers Mobility-Impaired

Reuters - Innovations Video Online (Dec. 21, 2014) A touch-free phone developed in Israel enables the mobility-impaired to operate smart phones with just a movement of the head. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Existing Chemical Compounds Could Revive Failing Antibiotics, Says Danish Scientist

Reuters - Innovations Video Online (Dec. 21, 2014) A team of scientists led by Danish chemist Jorn Christensen says they have isolated two chemical compounds within an existing antipsychotic medication that could be used to help a range of failing antibiotics work against killer bacterial infections, such as Tuberculosis. Jim Drury went to meet him. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins