季节性冻土路基工程温度场变化的数值模拟研究

Numerical Simulation Study on Change of Temperature Field in Seasonal Frozen Soil Subgrade Engineering

本文建立了青藏公路楚玛尔河路段某冻土路基工程的FLAC 3D数值模拟模型,分析了不同季节的阴阳坡效应和路基内部土体的温度变化规律,研究了温室效应对路基内部土体温度分布的影响规律。研究成果表明:(1)春夏秋冬环境条件下,阳坡和阴坡的温差分别为4℃、0℃、3℃和8℃;(2)在同一水平高度,路基内部土体的温差在夏季相差不明显、春秋季节较为明显、冬季最为明显;(3)温室效应会造成路基内部土体温度整体升高,导致路基土体的冻融交界线每10年会提升约0.6m。

In this paper, the FLAC 3D numerical simulation model of a permafrost roadbed project in chumar river section of qinghai-tibet highway was established. The yin-yang slope effect in different seasons and the temperature variation rule of soil inside the roadbed were analyzed. And the influence rule of greenhouse effect on the temperature distribution of soil inside the roadbed was studied. The results of the research showed that :(1)Under the environmental conditions of spring, summer, autumn and winter, the range of temperature between the sunny slope and the negative slope were 4℃, 0℃, 3℃ and 8℃ respectively.(2)At the same height level, There is no obvious difference in the range of temperature of soil mass inside subgrade, it was obvious in spring and autumn, and most invisible in winter;(3)Greenhouse effect would lead to the overall increase of soil temperature in subgrade, resulting in the freezing-thawing boundary of the roadbed soil which would increase to approximately 0.6 m every 10 years.