Figure 11
The illustration displays two sets of photos, labeled “a” at the top and “b” at the bottom, each arranged in a grid-like fashion. Both sets showcase the surface appearance of various concrete specimens, after being subjected to heat treatment, as indicated by the “400 degrees Celsius” label present on each individual specimen’s tag. Set “a,” in the upper portion of the image, consists of six photos arranged in two rows of three. Each photo shows a close-up of a concrete surface, which generally appears dark grey or brownish-grey with visible crack patterns and some surface irregularities or pores. A white rectangular label is affixed to the bottom-left of each specimen in this set, indicating the mix type and temperature: “C R-5 400 degrees Celsius”, “C R-10 400 degrees Celsius”, “C R-20 400 degrees Celsius”, “C R-30 400 degrees Celsius”, “C R-40 400 degrees Celsius”, and “C R-50 400 degrees Celsius”. The crack patterns and surface textures appear to vary slightly among these specimens. Set “b,” in the lower portion of the image, also consists of six photos arranged in two rows of three, mirroring the layout of set “a.” These photographs similarly show close-ups of concrete surfaces. The general appearance is also dark grey, with varying degrees of surface defects like cracks and pores. White rectangular labels are affixed to the bottom-left of each specimen in this set, indicating their mix type and temperature: “R 8-5 400 degrees Celsius”, “R 8-10 400 degrees Celsius”, “R 8-20 400 degrees Celsius”, “R 8-30 400 degrees Celsius”, “R 8-40 400 degrees Celsius”, and “R 8-50 400 degrees Celsius”. The visual characteristics of the surfaces in set “b” also exhibit some variation depending on the R 8 content.Surface (crack) damage of the SCB samples exposed at 400 °C (a) CR and (b) R8. Authors’ own work