Two-and-a-half years' safe operation of the Qinghai-Tibet railway has proven that China's technologies in building railways on frozen earth are ready to be used in more projects, a leading scientist said. The longest and highest railway in the world also received a State Special Award for Scientific and Technological Progress on Friday. "The set of technologies that solved problems about frozen earth and altitude sickness can benefit many other projects, such as the future Xinjiang-Tibet railway and the petroleum pipelines across Northeast China," Cheng Guodong, professor and president of Lanzhou branch of the Chinese Academy of Sciences, said in an interview. The technologies are also likely to make building an expressway on the Qinghai-Tibet Plateau possible, he said. The Ministry of Transport and Cheng's branch are currently doing research on the idea, but it is still in the very early stages, he said. "Technically it is possible, but building expressways are definitely more difficult than railways, because expressways are rigid and inflexible, not like rail tracks," he said. So far, the Qinghai-Tibet railway has operated safely and no fatal accidents have occurred since its opening on July 1, 2006, Sun Yongfu, former vice-minister of railways, said in an interview.   By last May, 1.48 million passengers have ridden the train into Tibet and 1.52 million out of Tibet, said Sun, who is also an academician with China Academy of Sciences. Though nearly half (550 km) of the railway is built on frozen earth - under-zero soil containing ice, which thaws in warm weather and causes the earth subsidence, data show the rail tracks on frozen earth subsided less than 2 cm each year. It is "quite an achievement", because controlling the subsidence within 30 cm can already be called the world's best record, he said. In Russia and Canada, which also have railways on frozen earth, serious subsidence has made trains run much slower than designed, at 50-70 kph. "Our trains have run at the designed speed of up to 100 kph," Sun said. The railway has also survived earthquakes that shook the Tangula area four times in June 2008. In the near future, a new railway will be built from Lhasa to Xigaze, and before 2020 a railway is planned connecting Xinjiang Uygur autonomous region and Tibet. In the long term, there will also be railways entering Tibet from Chengdu in Sichuan province and Kunming in Yunnan province, he said. In 2007, Tibet autonomous region gained 4.8 billion yuan from tourism revenue, up 73.3 percent year on year. Qinghai province gained 4.7 billion yuan, up 31.6 percent, according to official statistics.