Assessing Performance of Glow-in-the-Dark Concrete

The objective of this research was to develop a soy-based luminescent sealant for use on concrete surfaces. The luminescent sealant was a mixture of soy methyl ester polystyrene and strontium aluminate, a phosphorescent powder that slowly luminesces after being excited by light. A test procedure was developed to quantify the magnitude and duration of the luminance of the coated concrete surface; quantifying the luminance was key in evaluating the performance of the luminescent sealant. The luminescent sealant was excited in a consistent manner with a xenon lighting system that simulated sunlight, a photometer (light-measuring instrument) that measured the luminance of the excited concrete surface, and a housing unit that prevented extraneous light from the surroundings from influencing the test results. Results of the tests indicated that the luminescent surface emitted light (i.e., glowed) for approximately 24 h in a dark space after it was excited. Larger particles of strontium aluminate were found to luminesce for a longer time than did smaller particles. The excited sealant's luminance was independent of the amount of time it was exposed to light coming from the xenon lighting system.