摘要
为了维持多年冻土区路基的稳定,青藏铁路部分路段采用片石气冷—碎石护坡组合路基主动保护多年冻土。为考察片石气冷—碎石护坡组合路基片石层表面被风沙和积雪等封闭后,其降温效果是否失效,基于青藏铁路清水河地区片石气冷—碎石护坡组合路基2个测试断面、2个冻融循环的地温监测资料,研究片石层表面开放与封闭对片石气冷—碎石护坡组合路基降温效果的影响。结果表明：片石层表面封闭的片石气冷—碎石护坡组合路基及其基底平均地温比片石层表面开放的片石气冷—碎石护坡组合路基低0.16-0.23℃,负积温值封闭比开放大115.32℃.天,最大融化深度抬升幅度封闭比开放大0-0.4 m。说明片石层表面封闭的片石气冷—碎石护坡组合路基较开放的更有利于保护多年冻土,维持路基稳定;当片石气冷—碎石护坡组合路基片石层表面被风沙等封闭后仍具有良好的降温效果。
To solve embankment stability problem in permafrost area, in some sections of Qinghai-Tibet Railway, air-cooled riprap-crushed-rock revetment embankment subgrade was designed to protect permafrost. In order to research whether the cooling effect of air-cooled riprap-crushed-rock revetment embankment subgrade would be invalidated under the condition of the rock layer surfaces closed by sandstorm and snow, a field test, the air-cooled riprap-crushed-rock revetment embankment subgrades under the condition of the surfaces of opened and closed rock layer in permafrost regions of Qinghai-Tibet Railway were designed and conducted in Qingshuihe. Based on the monitoring data of ground temperatures for two sections after two freezing-thawing cycles, the influence on the cooling effect of these two kinds of embankments were analyzed comparatively. Results indicate that, compared with the air-cooled riprap-crushedrock revetment embankment subgrade under the condition of the surfaces of opened rock layer, the average temperature of subgrade and substratum of the air-cooled riprap-crushed-rock revetment embankment subgrade under the condition of the surfaces of closed rock layer is lower 0. 16-0.23℃, the minor accumulated temperature is bigger by 115.32 ℃· d, and the elevating range of the maximum thawing depth of embankment is bigger by 0-0. 4 m. Therefore, air-cooled riprap-crushed-rock revetment embankment subgrade under the condition of the surfaces of rock layer closed has more advantages in protecting permafrost and maintaining the stability of embankment. When the surfaces of air-cooled riprap-crushed-rock revetment embankment subgrade are closed by sandstorm or something else, it still has the good cooling effect.
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2008年第3期13-17,共5页
China Railway Science
基金
铁道部科技研究开发计划项目(2003G021)
关键词
青藏铁路
片石气冷—碎石护坡组合路基
开放
封闭
降温效果
试验研究
Qinghai-Tibet Railway
Air-cooled riprap-crushed-rock revetment embankment subgrade
Open
Close
Cooling effect
