用冷却路基的原则修建青藏铁路  

CONSTRUCTING OF QINGHAI-TIBET RAILROAD BY COOLING THE ROADBED

作　　者：程国栋[1] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所冻土工程国家重点实验室,兰州730000

出　　处：《科技导报》2005年第1期4-8,共5页Science & Technology Review

基　　金：中国科学院知识创新工程重大项目(KZCX1-SW-04);国家自然科学基金重大项目(90102006);"973"国家重点基础研究发展规划项目(2002CB412704)

摘　　要：青藏铁路将要穿越的多年冻土半数以上属高温冻土,有40%为高含冰量冻土。在全球转暖的情况下,青藏铁路的修建必须考虑50～100年的气候变化。最近的预测认为:至2050年青藏高原将升温2.2～2.6℃。因而,铁路成败的关键在于能否保护多年冻土使其不融化。世界上在冻土区筑路己有百年以上的历史,但报道的冻土区铁路的病害率平均在30%以上。根据国内外在多年冻土区筑路的经验和教训提出:青藏铁路的设计应该改变单纯依靠增加热阻(增加路堤高度,使用保温材料)消极的保护冻土的思路,而应全面采用“冷却路基”积极的“降低地温”的原则,特别是在高温、高含冰量地段必须如此;进一步提出了通过改变路堤的结构和材料来调控辐射、调控对流和调控传导,以达到“冷却路基”目的的具体措施。More than half of the total length of Qinghai-Tibet Railroad (QTR) traverses warm (0～1°C) permafrost areas, and about 40% of its total length is in ice-rich permafrost areas. The construction of the QTR must also consider the impacts of climatic warming along the QTR during the next 50～100 years. The latest projection indicates a warming of 2.2～2.6°C 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 the railroad roadbed by lowering permafrost temperatures should be used in the design of the QTR, rather than that of 'passive protection' of permafrost through increasing thermal resistance of the 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.

关 键 词：青藏铁路 路基 筑路 多年冻土区 冻土区 路堤 修建 地段 原则 增加 

分 类 号：U213.1[交通运输工程—道路与铁道工程]