冬季高速公路路桥温度变化规律及能量平衡分析

利用2009年10月-2010年3月湖北省武英高速凤凰关水库自动气象站逐时路、桥面温度和常规气象资料，分析了冬季典型天空状况（晴空、阴天）和天气过程（雾、降雨、降雪）中气温、路面温度和桥面温度的变化规律。结果表明，夜间桥面温度与气温接近，比路面温度低2℃，桥面0℃以下的低温维持时间为路面维持时间的2倍左右。利用下垫面能量平衡模型，分别计算冬季夜间晴空和阴天时路、桥面辐射能量收支变化情况，分析了夜间路面和桥面温度变化差异的原因，并对桥面比路面更易结冰的现象给出了理论解释。

Characteristics of bridge and road surface temperature changes in winter and energy budget analysis

Based on the observations of road and bridge surface temperature and conventional meteoro- logical data from Fenghuangguan reservoir automatic weather station along Wuying expressway from October 2009 to March 2010, the hourly variations of air temperature and bridge and road surface tem- perature were studied under different weather conditions including clear, overcast, foggy, rainy and snowy. The results showed that the bridge surface temperature was close to the air temperature and was usually 2 ℃ lower than the road surface temperature at night in winter. Moreover, surface freezing hours over the bridge is almost twice as long as that on the road. By using the validated underlying surface en- ergy balance model, we calculated the energy budget elements of bridge surface at night under clear and overcast weather conditions respectively in winter, analyzed the difference in temperature changes be- tween road and bridge surface and tried giving explanations for the phenomenon that bridge surface is apt to freeze compared with road surface.