Effect of amount of pigment on the solar reflectance of mortars for the production of cool colored concrete tiles
DOI:
https://doi.org/10.46421/encacelacac.v18i1.6754Keywords:
Cool roof, Solar absorptance, Cement-based materials, Titanium dioxide, Iron oxideAbstract
This paper determines the optimal amount of pigment for the production of Brazilian cool concrete tiles. Spectral reflectance measurements were conducted on 60x60x11 mm pigmented mortar samples, and the Solar Reflectance Index (SRI) was calculated for them. White, yellow, red, brown, and black pigments were added to the mortars at 1%, 5%, and 10% of the cement weight. Solar reflectance (SR) increased with the addition of white pigments, showing a very strong correlation (r=0.952). On the other hand, yellow, red, brown, and black pigments reduced the SR as their concentration increased. Although no mortar had an SRI > 78 to be classified as a cool roof, it is recommended to use 10% and 1% of the cement weight for white and colored pigments, respectively, to achieve higher SR rates in colored concrete tiles.
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