季节性冻土地区公路路基冻融过程实时监测分析

在典型季节性冰冻气候区公路路基内埋设温度传感器及单点位移计,采用无线远程自动传输装置,获取了一个完整冻结-融化周期内路基冻融过程实时监测数据,定量分析了路基冻结-融化时间、降温升温幅度、降温升温速率及分层冻胀量和总冻胀量特征,指出下路床下部及有水源补给的冻深线末端是发生冻胀的主要层位,春融期上下冻层双向融化产生的软弱夹层会导致路基承载力下降,应作为冻害防治考虑的重点,对路基冻融机理分析和冻害防治具有重要的参考意义。

Analysis on Real-time Monitoring for Freezing and Thawing Process of Highway Subgrade in Seasonal Frozen Soil Area

By laying temperature sensor and single point extensometer in subgrade of highway in typical area of seasonal frost climate, with wireless remote communication link, the data of real-time monitoring on a complete freezing-thawing cycle in the subgrade was obtained, based on which the characteristics thereof, including the freezing and thawing time, the temperature rises and drops, the warming and cooling speed, the frost-heave capacity in each layer and in total, were studied by quantative analysis.From the studies, it was found that the lower part of the roadbed and the end of frost line with water supply were the main positions where frost-heave arises, and the weak intercalated layer arising out of two-way thawing between the upper and lower frozen layers in spring-thawing period, which may lead to reduced bearing capacity of subgrade, should be the concern in frost damage prevention, which may be the important reference to analysis of subgrade freezing-thawing mechanism and control of frost damage.