Figure 17
Two thermal infrared images labeled “a” and “b” display fire resistance tests conducted on large concrete wall panels placed vertically against a brick wall. Each panel consists of a grid of rectangular compartments arranged in three rows and three columns, with differing materials or treatments. In both images, the thermal data is visualized using a color gradient ranging from blue (cool) to red and yellow (hot). In both panels, the top row of sections appears predominantly yellow-green, indicating moderate surface temperatures, while the middle and bottom rows contain brighter red and blue areas with defined rectangular or square zones, indicating significantly higher heat retention in those regions. In image “a,” the thermal data is recorded at the timestamp “23 slash 09 slash 20 12:52,” with the thermal counter box displaying “10 s” and “744 slash 1000,” overlaid in gray in the upper-right quadrant of the wall. The vertical color scale on the right shows the color variation from blue at the bottom, marked as “21.7 Auto,” to red at the top, marked as “134.9.” The thermal imaging parameters are shown at the bottom left as “epsilon equals 0.92” and “R T equals 17.4 degrees Celsius.” Several power cables, yellow wires, and testing apparatus are visible on the ground below the wall, including a black spotlight angled upward on the bottom right. The setup is positioned in front of a partially exposed brick wall. In image “b,” taken on “23 slash 10 slash 06 12:30,” the thermal indicator shows “10 s” and “755 slash 1000,” again in the upper-right section. The vertical color scale on the right shows the color variation from blue at the bottom, marked as “32.9 Auto,” to red at the top, marked as “163.8.” The average surface temperatures differ, with larger areas in yellow and red, indicating intense heat zones within the central wall blocks. The thermal parameters are shown at the bottom left as “epsilon equals 0.92” and “R T equals 19.3 degrees Celsius.” Similar yellow wiring is visible on the ground, along with a black testing device positioned directly in front of the wall base. The test environment includes orange and white equipment boxes along the right edge and some visible structural features such as pipes and panels around the testing area.Temperature distribution of the wall surfaces obtained from thermal imager (a) CR and (b) R8. Authors’ own work