热棒对多年冻土路基稳定性的影响  

Influences of Two-phase Closed Thermosyphon on Permafrost Roadbed Stability

作　　者：孙文[1] 吴亚平[1] 郭春香[1] 张鲁新 

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070 [2]青藏铁路公司,青海西宁810007

出　　处：《中国公路学报》2009年第5期15-20,共6页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(50678076);"十一五"国家科技支撑计划重点项目(2006BAC07B02)

摘　　要：建立了多年冻土路基温度场的三维数值计算模型,并采用有限元方法对普通路基、热棒路基在未来50年内气温上升2.6℃情况下的温度场进行了预报分析和比较,研究中考虑了路基阴阳坡差异,并以现场实测地温数据为依据。计算结果表明:路基阴阳坡的热差异会导致路基下伏土层温度场不对称,由此可引起路基横向的不均匀变形;在气温升高条件下,未来50年内普通路基将会产生较大融沉变形,不能保证路基的长期稳定性,加热棒后的路基融化深度均小于普通填土路基的融化深度,阴阳坡温度差异也有明显降低,说明热棒结构路基可以抵消气候变暖的影响,从而可以保证路基的稳定性。A 3-D numerical value calculation model of the permafrost roadbed thermal field was built and finite element method was adopted to predict and compare the thermal field of general roadbed and two-phase closed thermosyphon roadbed by rising 2. 6 ℃ in the coming 50 years. Difference of the negative and positive slope of roadbed was considered in studying and the measured data of ground temperature with the scene was regarded as the foundation. The calculated results show that the thermal difference of the negative and positive slope can cause asymmetry of soil layer temperature field under roadbed, which will arouse uneven transverse deformation of roadbed. Under the condition of rise of air temperature, the general roadbed may come into bei term stability smaller than obviously. It the influence ng melt settlement deformation in the coming 50 years and can＇t guarantee the long- of roadbed. The thawing depth of two-phase closed thermosyphon of roadbed is that of general roadbed and the difference of negative and positive slope reduces explains that the two-phase closed thermosyphon structure roadbed can counteract of climate being changed into warm and can guarantee the roadbed stability.

关 键 词：道路工程 多年冻土 有限元方法 温度场 热棒 稳定性 

分 类 号：U416.168[交通运输工程—道路与铁道工程]