多年冻土地区路基温度场的数值模拟研究

Numerical Simulation of Subgrade Temperature Field in Permafrost Regions

本文以五道梁地区典型路基为研究对象,对多年冻土地区路基温度场进行数值模拟,研究了不同上垫面类型对路基温度场的影响。结果表明:季节冻结过程的特点主要是单向冻结和双向融化,上边界负温变化大而下边界正温变化小,冻深主要受上边界制约。季节融化过程特点则是单向融化和双向冻结,上边界为正温变化大,下边界为负温变化小,同样主要受上边界制约。位于多年冻土地区的水泥路面结构可把路面的年均温度降低到2.2℃左右。受全球气候变暖的影响,路基各边界处年均温度均呈现上升的趋势,各边界升温速率从快到慢排序依次为:沥青路面、水泥路面、阳坡、天然地面、阴坡。

Taking the typical subgrade of Wudaoliang area as the research object,the numerical simulation of the subgrade temperature field in permafrost regions was carried out, and the influence of different types of upper surface on the subgrade temperature field was studied. The results show that the characteristics of the seasonal freezing process are one-way freezing and two-way melting. The upper boundary negative temperature changes greatly and the lower boundary positive temperature changes little. The freezing depth is mainly restricted by the upper boundary. The seasonal melting process is characterized by one-way melting and two-way freezing. The upper boundary has a large positive temperature change and the lower boundary has a small negative temperature change. The freezing depth is also mainly restricted by the upper boundary. In permafrost regions,the cement pavement structure can reduce the annual average temperature of the pavement by about 2.2 ℃. Influenced by global warming,the annual average temperature of each boundary of the subgrade presents a rising trend,and the rising speed of each boundary temperature from fast to slow is:asphalt pavement,cement pavement,sunny slope,natural ground,shady slope.