中文摘要：

根据青藏高原多年观测资料,运用ANSYS有限元计算软件对多年冻土区铁路路堤的合理高度进行研究。结果表明：路堤临界高度与多年冻土区大气年平均温度有密切的关系,随着大气年平均温度的升高,路堤的下临界高度逐渐增大,而上临界高度逐渐减小;路堤的上临界高度恰好等于下临界高度时的临界大气年平均温度为-3.43℃,高于此温度时,多年冻土区铁路的路堤不存在临界高度;当大气年平均温度分别为-3,-4,-5和-6℃时,对应的路堤下临界高度分别为5.88,3.83,3.12和2.60 m,而路堤上临界高度分别为4.59,5.20,6.29和6.97m;计算值与实测值基本吻合,验证了采用有限元计算方法是合理的,计算结果能够反映实际情况。

英文摘要：

Based on the many-year observation data of Qinghai-Tibet plateau,the reasonable height of railway embankment in permafrost region was studied with ANSYS finite element analysis software.Results show that the critical height of railway embankment has a close relationship to the mean annual atmospheric temperature of permafrost region.With the increase of the mean annual atmospheric temperature,the lower limits for the critical heights of embankment gradually increase,but the upper limits for critical heights gradually decrease.The critical value of the mean annual atmospheric temperature is-3.43 ℃ when the upper limit for critical height is just equal to the lower limit.If the mean annual atmospheric temperature is higher than-3.43℃,the critical height of railway embankment does not exist in permafrost region.When the atmospheric temperature is-3 ℃,-4 ℃,-5 ℃ and-6 ℃respectively,the corresponding lower limits for the critical heights of embankment are 5.88,3.83,3.12 and 2.60 m,while the corresponding upper limits for critical heights are 4.59,5.20,6.29 and 6.97 m.The calculated values basically agree with the measured ones,which indicates that the finite element method is reasonable and the actual conditions can be well reflected by calculated results.