通风管-块石复合路基降温效果的数值分析  

Numerical analysis of the cooling effect of an embankment with ventilated ducts and closed block stones

作　　者：张坤[1] 李东庆[1] 童刚强[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：《中国矿业大学学报》2011年第1期35-42,共8页Journal of China University of Mining & Technology

基　　金：中国科学院西部行动计划(二期)项目(KZCX2-XB2-10);国家自然科学基金项目(40671039;41001041);国家高技术研究发展计划(863)项目(2008AA11Z103);冻土工程国家重点实验室基金项目(SKLFSE-ZY-03)

摘　　要：在考虑未来50 a气温上升1℃的情况下,通过数值模拟来研究通风管-块石(封闭)新型复合路基的降温效果.结果表明:普通路基下冻土上限从第1年的-1.86 m下降到第50年的-4.85 m;50 a后,普通通风管路基和封闭块石路基下部多年冻土的0℃等温线分别位于天然地表下-0.89 m和-0.22 m处,通风管-块石(封闭)路基下部0℃等温线在50 a内始终高于天然地表,第50年的0℃等温线位于天然地表之上0.04 m处;在暖季,通风管-块石(封闭)路基与天然地表交界面的正热流密最小,普通通风管路基中的通风管热流密度为正,而通风管-块石(封闭)路基中的通风管热流密度为负,这表明复合路基中封闭块石弥补了通风管暖季吸热的缺陷;在高温高含冰量地区推荐使用通风管-块石(封闭)路基作为公路路基结构.A new type composite roadway embankment having ventilated ducts and closed blocks was studied under the assumption of an average air temperature rise of one degree Centigrade over the next fifty years.The permafrost table is predicted to drop 1.86 meters in the first year and 4.85 meters in the fiftieth year if a traditional embankment is used.The ordinary ventilation duct and closed block stone embankments are predicted to have upper zero degree isotherms in the permafrost at 0.89 and 0.22 meters below the natural surface after fifty years.The ventilation duct,closed block stone embankment 0 ℃ isotherm is always higher than the natural surface after 50 years.The fiftieth year 0 ℃ isotherm is located 0.04 m above the natural surface.In the warm season the heat flux across the interface between the ventilation duct,closed block stone embankment and the natural ground surface is the smallest.The heat flux of an ordinary ventilation duct embankment is positive while that of the closed block stone embankment is negative.This shows that the composite closed block stone can make up for deficiencies from heat absorption in the summer.The ventilation duct,closed block stone embankment is recommended as a highway embankment structure in permafrost areas of high temperature and high ice content.

关 键 词：通风管-块石(封闭)路基 普通通风管路基 封闭块石路基 温度场 全球变暖 

分 类 号：U416.12[交通运输工程—道路与铁道工程]