Mitigation Effect of Thermal Environment on the Asphalt by Sprayed Water

In this study, water was sprinkled on the asphalt surface during the hottest hours of the day using a sprinkler, and the effect was experimentally verified. An air temperature, a humidity, a ground surface temperature, and a globe temperature which is radiant heat from the ground were measured, and using these measurements, WBGT (Wet-Bulb Globe Temperature), which is an index of thermal stress on the human body, was calculated. In this way, we investigated not only the climate mitigation effect but also the mitigation effect of the thermal environment felt by the human body.
As a result, the following points were clarified in this study: 1) During sprinkling, the air temperature, the black globe temperature, and the WBGT were lower in the sprinkled area than in the controlled area, and the wet-bulb temperature hardly changed. 2) Focusing on the amount of change after watering compared to before watering, the air temperature, the globe temperature, and the WBGT decreased, and the wet-bulb temperature hardly changed. 3) In the sprinkled area, when the WBGT value just before watering is higher than that of the strict caution (WBGT is 28°C or higher), it drops to a level one rank lower, and when the WBGT value just before watering is warning (WBGT value is 25°C or higher), it was almost no change.

研究論文　環境管理工学科