多年冻土区块、碎石护坡冷却作用的对比研究  

Experimental Study on Cooling Effect of Air Convection Embankment with Crushed Rock Slope Protection in Permafrost Regions

作　　者：孙志忠[1] 马巍[1] 李东庆[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,甘肃兰州730000

出　　处：《冰川冻土》2004年第4期435-439,共5页Journal of Glaciology and Geocryology

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);国家重点基础研究发展规划项目(2002CB412704)资助

摘　　要：基于青藏铁路北麓河试验段块、碎石护坡路基阳坡坡中孔的地温观测资料,分析了块、碎石护坡下的温度变化过程及进入块、碎石层下部土体的热收支情况.结果表明:观测期内块石层下平均温度低于碎石层下平均温度,而块石层下温度波幅大于碎石层下温度波幅.块石层下最大融化深度有明显的抬升,这种抬升得益于冷季块石层内空气较强的对流冷却作用.从进入块、碎石层下部土体的热收支情况来看,块石层较碎石层具有更好的冷却作用.During 2001_2003, an experimental air convection embankment (ACE) was constructed in Beiluhe Test Field in the Tibetan Plateau. The embankment is built on permafrost foundation with thick ground ice. Both slopes of the embankment were filled in with poorly sorted coarse (5～8 cm and 40～50 cm) crushed rock. It should be called air convection embankment with crushed rock slope protection (ACE-CRSP). The highly permeable ACE-CRSP installation was designed to test the cooling effect of ACE-CRSP concept in a real railway project. Ground temperatures were collected from test sections by sing thermistor sensors. In this paper, based on the ground temperatures taken in the boreholes within the south block-rock and crushed stone slopes, the temperature change was analyzed for different rock diameters and different heat budgets into soil body. The result shows that the mean ground temperature under the block-rock layer is lower than that under the crushed stone layer, and the temperature fluctuating range is larger under the former than that under the latter. It is obvious that the maximum depth of thawing rises under the block-rock layer, which results from the stronger cooling effect of its convection during wintertime. The amount of heat budget displays that for supplying cold energy, the block-rock layer is better than the crushed stone one.

关 键 词：块石 碎石 冷却作用 热收支 

分 类 号：P642.14[天文地球—工程地质学]