Effects of composition and exposure on the solar reflectance of portland cement concrete

TitleEffects of composition and exposure on the solar reflectance of portland cement concrete
Publication TypeJournal Article
Year of Publication2002
AuthorsLevinson, Ronnen M., and Hashem Akbari
JournalCement and Concrete Research
Volume32
Pagination1679-1698
KeywordsCool Pavements, Heat Island
Abstract

Increasing the solar reflectance (albedo) of a paved surface keeps it cooler in the sun, reducing convection of heat from pavement to air and thereby decreasing the ambient air temperature. Lower air temperatures decrease demand for cooling energy and slow the formation of urban smog. Variations with composition and environmental exposure of the albedos of portland cement concrete pavements were investigated through laboratory fabrication and exposure of 32 mixes of concrete. Concrete albedo generally correlated with cement albedo and sand albedo and, after abrasion, with rock albedo. Cement albedo had a disproportionately strong influence on the reflectance of concrete. Simulated weathering, soiling, and abrasion each reduced average concrete albedo, though some samples became slightly more reflective through weathering or soiling. Concrete albedo grew as the cement hydration reaction progressed, but stabilized within six weeks of casting.

Notes

0008-8846Added to JabRef: 2010.04.19

URLhttp://dx.doi.org/10.1016/S0008-8846(02)00835-9
DOIDOI: 10.1016/S0008-8846(02)00835-9