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China's Ministry of Railways will take measures to deal with problems relating to cracking and heaving caused by permafrost along the Qinghai-Tibet Railway, said Vice Minister Song Yongfu Wednesday.

Speaking at the Asian International Permafrost Conference in Lanzhou, capital of northwest China's Gansu Province, Sun said the Ministry of Railways will further study the effect of temperature increases and train loads on the permafrost. Permafrost is ground that is permanently frozen and is prone to heaving as temperatures fluctuate.

"We have already established a long-term inspection system of the permafrost and will solve problems in a timely fashion," the official said.

About 550 kilometers of the world highest railway was built on permafrost earth in the Qinghai-Tibet Plateau.

China's Ministry of Railways Spokesman Wang Yongping said earlier that the foundation of the railway was sinking and cracking in some sections and that cracks have been seen on some of the railway structures and bridges.

Cheng Guodong, of the China Academy of Sciences, said starting to run trains on the Qinghai-Tibet Railway was not the final success.

"There remain some problems to solve, such as issues relating to permafrost," Cheng said.

He said the major problems concerning the Qinghai-Tibet Railway are partial foundation cracking and water accumulation, and that cracking happens where cooling techniques are not applied.

"Current problems are merely on the surface, which can be solved with normal maintenance, and the stability of the railway foundation is not affected," he said at the Asian International Permafrost Conference held here from August 7 to 9.

"The Qinghai-Tibet Railway represents the latest development of permafrost engineering," said Jerry Brown, president of the International Permafrost Association. "Other countries can learn from China's achievements in this field."

Yet international experts agreed that permafrost engineering, including the Qinghai-Tibet Railway, faces complicated problems and needs further exploration.

"The Siberian Railway has been running for over 100 years, yet stability problems remain," said Professor Valentin Kondratiev from Russia. "It is little wonder the magnificent Qinghai-Tibet Railway would suffer some problems."

American permafrost engineering expert Max Brewer said that the Alaska Railway, which also runs over permafrost was built in 1923. "It is naive to expect such a long railway not to encounter problems," he said.

Security measures have already been put in place to protect the Qinghai-Tibet Railway. "We have installed a long-term permafrost monitoring system in order to settle new problems," said Vice Minister of Railway Sun Yongfu in a written speech.

"As for deformities of the permafrost foundation, we will take timely measures to repair them," Sun said. "As for the impact of global warming and repeated loading, we will conduct further research."

Chinese engineers are carrying out detailed examinations and maintenance along the Qinghai-Tibet Railway, and plan to develop some effective emergency measures.

"The opening of the Qinghai-Tibet Railway does not mean an ultimate success, nor will the permafrost problems be solved once for all," said Cheng Guodong. "Measures will be continuously taken, and we are confident we can ensure the safety and stability of the Qinghai-Tibet Railway."

(Xinhua News Agency August 10, 2006)