Studies on the temperature distribution of steel plates with different paints under solar radiation

• Solar radiation absorptions for steel with different paintings were measured.
• The temperatures of all specimens under solar radiation were measured.
• The effect of color, thickness and painting type on solar absorption was analyzed.
• A numerical analysis was conducted and verified by test data.
• A simplified formula was deduced and verified by test data.

Thermal effects on steel structures exposed to solar radiation are significant and complicated. Furthermore, the solar radiation absorption coefficient of steel surface with different paintings is the main factor affecting the non-uniform temperature of spatial structures under solar radiation. In this paper, nearly two hundreds steel specimens with different paintings were designed and measured to obtain their solar radiation absorption coefficients using spectrophotometer. Based on the test results, the effect of surface color, painting type, painting thickness on the solar radiation absorption coefficient was analyzed. The actual temperatures under solar radiation for all specimens were also measured in summer not only to verify the absorption coefficient but also provide insight for the temperature distribution of steel structures with different paintings. A numerical simulation and simplified formula were also conducted and verified by test, in order to study the temperature distribution of steel plates with different paints under solar radiation. The results have given an important reference in the future research of thermal effect of steel structures exposed to solar radiation.