街路形態に応じたヒートアイランド対策技術の適材適所の導入検討に関する研究

Abstract

Abstract In this study, we analyzed the effects of introducing urban heat island measure technologies in a typical street canyon model to aid the selection of a suitable technology. It is appropriate to use street trees for improving the thermal environment of a sidewalk and high reflectance paint or water-retentive pavement for the reduction of surface temperature on the roadway. Reduction of solar radiation gain to the sidewalk pavement surface depends on the location and area of the street tree shadows, which are likely to occur on the northern sidewalk of an east–west road rather than an eastern (or a western) sidewalk of a north–south road. Moreover, the area of the shadow is proportional to the square of the width of tree crown (the radius) and inversely proportional to the distance between trees. Thus, it is necessary to prioritize these considerations based on the road orientation and time when the pedestrian use of sidewalk is the highest.