钢结构常用涂料太阳辐射吸收系数试验研究

Experimental research on solar radiation absorptance of commonly used coatings for steel structures

大跨度钢结构受太阳辐射作用,温度场具有非均匀性和时变性,结构的温度效应异常复杂。工程中低估温度效应会影响结构安全从而导致焊缝开裂、结构坍塌等工程事故。钢结构常用涂料的太阳辐射吸收系数是进行太阳辐射作用下钢结构温度效应分析的关键因素。在总结文献的基础上,提出了基于光谱法的采用分光光度计测定涂料太阳辐射吸收系数的方法。通过测定及分析17组样品的太阳辐射吸收系数,确认面漆的颜色是影响太阳辐射吸收系数的主要参数。基于试验测定的太阳辐射吸收系数,通过对山东茌平体育馆屋盖的简化算例分析,分别研究了6种常用面漆涂装的大跨度空间结构的温度场及其温度响应。结果表明,钢构件表面所采用的面漆颜色对太阳辐射下的结构温度场和温度效应具有较大的影响。

For long span steel structures exposed to the solar radiation,the temperature fields of the structures show the features of heterogeneity,time variation and complicacy. However,the temperature effect on structures is often underestimated,resulting in weld failure or even the collapse of structures. The solar radiation absorptance of the commonly used coatings are the key factor in studying the temperature effect of the solar radiation on steel structures. On the basis of document research,a method of measuring the solar radiation absorptance by the spectrophotometer is adopted,which is based on the principle of spectrometry. A total number of 51 specimens classified into 17 groups were studied,and the solar radiation absorptance of different coatings were measured in tests. A conclusion that the color of topcoating is the key factor to the solar radiation absorptance is reached. The temperature fields and temperature effects of the Chiping Gymnasium roof structure with six different coatings were studied based on the solar radiation absorptance obtained in tests. The results show that the topcoating color of the steel components has great influence on the temperature fields and temperature effects of structures under solar radiation.