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介绍一种测试寒区路基反射率的试验方法,测试路基模型的反射率,并将实测模型表面反射率与ASTME1918A规范计算结果进行对比。研究结果发现:ASTM-E1918A测试方法是该文中模型的一个特例。当太阳辐射瞬时强度值变化小于20 W/m~2时,模型计算的反射率与ASTM-E1918A测量值的偏差在0~0.2之间,因为ASTME1918A忽略云层变化引起的太阳辐射瞬时强度变化,因此ASTM-E1918A方法不适合在阴天多云条件下测量曲面的反射率,而该文的方法适用于任意气象条件下的路基表面反射率测量,既可满足实际测试和工程使用的要求,又可提高测量反射率精度。
A test method for testing the reflectivity of subgrade in cold region was introduced to test the reflectivity of the subgrade model. The surface reflectivity of the measured model was compared with the calculated results of ASTM E1918A specification. The study found that: ASTM-E1918A test method is a special case of the model in this article. When the instantaneous change of solar radiation is less than 20 W / m ~ 2, the difference between the calculated reflectance and the measured value of ASTM-E1918A is between 0 and 0.2. Because ASTME1918A ignores the change of instantaneous solar radiation intensity caused by cloud change, The method of ASTM-E1918A is not suitable for measuring the reflectivity of curved surface under cloudy and cloudy conditions. The method of this paper is suitable for the measurement of subgrade surface reflectivity under any weather conditions, which can not only meet the requirements of actual test and engineering but also improve Reflectance accuracy is measured.