摘要
采用稳态比较法,对铁路碎石道碴层的导热系数进行了测试.试验在常温条件下,分别对底部加热及顶部加热两种情况进行了研究.结果表明:当碎石道碴层顶、底面之间的温差较小时,顶部加热及底部加热两种试验条件下测得的导热系数基本相同;而当碎石道碴层顶、底面温差较大时,底部加热条件下的导热系数明显地大于顶部加热条件下的导热系数.在底部加热条件下,碎石道碴层的导热系数随温差的增大而逐渐增大.碎石道碴层具有吸热和放热条件下传热的不对称性,合理地利用碎石道碴层的这一传热特性,可望对路基下多年冻土起到积极的保护作用.
In this paper, the thermal conductivity of railway ballast is measured by steady comparison method. The experiment was carried out at room temperature and two thermal conditions, heated from below and from above, were studied. The test results show that the thermal conductivity of the railway ballast is almost the same for the two thermal conditions when the temperature difference between the top and bottom of the ballast is smaller. When the temperature difference of the ballast is larger, however, the thermal conductivity for the condition of being heated from below is greater than that of being heated from above. Moreover, under the condition of being heated from below, the thermal conductivity increases with increasing temperature difference between the top and bottom of the ballast. It means that the heat transfer in the railway ballast is dissymmetric for the two thermal conditions. For the engineering of railway construction in cold regions, it is hoped that the permafrost under the railway embankment can be protected and reinforced if this advantage of heat transfer in railway ballast is taken.
出处
《冰川冻土》
CSCD
北大核心
2003年第6期628-631,共4页
Journal of Glaciology and Geocryology
基金
中国科学院寒区旱区环境与工程研究所知识创新工程项目(CACX210071)
中国科学院"百人计划"项目
铁道部科技开发计划项目(2001G001 A 02)
中国科学院知识创新工程重大项目(KZCX1 SW 04)资助
