Painting the roadway embankment with non-white high reflective pigments to raise the albedo

Abstract

Roadway in permafrost regions usually needs embankments to disperse the traffic stresses to the underlying layers. As a bent surface, the diffuse reflections leaving the surface may return to it, increasing the solar absorption of the embankment. The purpose of this study is to illustrate the possibility of raising the embankment section’s albedo as a strategy to cool the roadbed. This study searched for a group of non-white pigments with high reflectivity for the near-infrared light but low reflectivity for the visual and ultraviolet light. These pigments were painted on the surface of the embankment model, whose albedo was estimated by a proposed procedure for measuring the albedo of a bent surface. It is found that increasing the embankment surface albedo of 0.10 could raise the embankment albedo of 0.09. The residual 0.01 is because multiple reflections between the embankment side slope and its adjacent ground increase the side-slope solar absorption. Further experiments are expected to measure the albedo of bare soils and crushed rock layers with high reflective non-white pigments painted.