摘要
More than half of the total length of the Qinghai-Tibet Railroad (QTR) traverses warm (0 to-1 ℃) permafrost areas, and about 40% of its total length is in ice-rich permafrost areas. The construction of the QTR also must consider the impacts of climatic warming along the QTR during the next 50～100 years. The latest projection indicates a warming of 2.2 to 2.6 ℃ on the Qinghai-Tibet Plateau (QTP) by the year 2050. Therefore, the key to the successful construction of the QTR is to protect permafrost from being thawed. Although railroad construction in permafrost areas has had a history of more than 100 years, the troubled sections of the railroads in permafrost areas have been greater than 30% of their total length. Based on the experiences and lessons learned from the road construction in permafrost areas, both in China and abroad, the author proposes that the principle of'active cooling'of railroad roadbed by lowering permafrost temperatures should be used in designing QTR, rather than that of'passive protection' of permafrost through increasing thermal resistance of roadway, such as increasing fill thickness and/or using insulative materials. This is especially important for the road sections in warm, ice-rich permafrost. In addition, this paper proposes several methods for'cooling the roadbed' by controlling radiation, convection and conduction through modifying roadway structure and using different fill materials.
More than half of the total length of the Qinghai-Tibet Railroad (QTR) traverses warm (0 to {-1} ℃) permafrost areas, and about 40% of its total length is in ice-rich permafrost areas. The construction of the QTR also must consider the impacts of climatic warming along the QTR during the next 50~100 years. The latest projection indicates a warming of 2^2 to 2^6 ℃ on the Qinghai-Tibet Plateau (QTP) by the year 2050. Therefore, the key to the successful construction of the QTR is to protect permafrost from being thawed. Although railroad construction in permafrost areas has had a history of more than 100 years, the troubled sections of the railroads in permafrost areas have been greater than 30% of their total length. Based on the experiences and lessons learned from the road construction in permafrost areas, both in China and abroad, the author proposes that the principle of !active cooling' of railroad roadbed by lowering permafrost temperatures should be used in designing QTR, rather than that of !passive protection' of permafrost through increasing thermal resistance of roadway, such as increasing fill thickness and/or using insulative materials. This is especially important for the road sections in warm, ice-rich permafrost. In addition, this paper proposes several methods for !cooling the roadbed' by controlling radiation, convection and conduction through modifying roadway structure and using different fill materials.
出处
《冰川冻土》
CSCD
北大核心
2005年第1期1-7,共7页
Journal of Glaciology and Geocryology
基金
This work was supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (KZCX SW 04)
关键词
青藏铁路
路基
原理
冷却
基原
建设
Qinghai-Tibet Railroad
permafrost
active cooling
roadbed
climatic warming
