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为了揭示地气温影响下青藏高原多年冻土区宽幅路基内的复杂耦合换热机理,针对典型工况条件下冻土路基内温度场的分布特征及其随时间的变化规律开展了数值研究。将冻土路基的外部环境影响纳入研究模型,通过建立统一的地气耦合系统的二维非稳态计算模型,分析了路面宽度、风速、路基高度和走向等因素对冻土路基各表面温度年际变化特征的影响规律。研究结果表明:路基各表面的温度均大致呈正弦变化趋势,其中沥青路面始终保持较高温度,而天然地表温度在5月上旬和10月上旬出现明显阶跃变化;随着路面宽度的增加,路基各表面的年平均温度随之增加,而随着风速及路基高度的增加而降低,其中尤以沥青路面及两侧土路肩处的降低趋势最为明显;路基边坡处的年均温度与路线走向密切相关,在3种路线走向中,东西走向路基的右侧坡面和左侧坡面年平均温度分别出现最大值和最小值。
In order to reveal the mechanism of complex coupled heat transfer in the broad subgrade of the Qinghai-Tibet Plateau under the influence of ground temperature, the distribution of temperature field and its variation with time under typical working conditions are numerically studied. The influence of external environment of permafrost embankment is included in the research model. Through the establishment of a two-dimensional unsteady calculation model of the unified ground-air coupling system, the influence of various factors such as pavement width, wind speed, subgrade height and direction on the surface temperature The Influence Law of International Variation. The results show that the temperature of each surface of the roadbed changes roughly sinusoidally, of which the asphalt pavement always maintains a higher temperature, while the natural surface temperature shows obvious step changes in early May and early October. With the increase of pavement width, The average annual temperature of each surface of subgrade increases with the increase of wind speed and subgrade height, especially the decreasing tendency of asphalt pavement and shoulder of soil on both sides is the most obvious. Are closely related to the trend of the three kinds of routes, the maximum and minimum values of the annual average temperature of the right slope and the left slope of the subgrade to the east and west respectively appear.