Numerical Investigation on the Cooling Performance of the Embankment with Grey NIR Reflective Coating and Sun/Snow Shield in Arctic Permafrost Regions

Solar radiation and snow accumulation are the two important factors impacting thermal states of the permafrost beneath embankments with asphalt pavement in the Arctic regions, which can threaten the stability of permafrost and thus operation safety. In this study, we adopted the numerical simulation method to evaluate and compare the cooling performance of the proposed three types of embankments, namely, grey near-infrared reflective coating embankment, sun/snow shield embankment, and grey near-infrared reflective coating–sun/snow shield embankment, thereby mitigating the effect of the solar radiation and snow accumulation in the Arctic regions. Results show that (1) the grey near-infrared reflective coating mainly cools permafrost underlying the asphalt pavement and cannot mitigate thermal imbalance issue of two sides in embankment (shady–sunny slope effect), while the sun/snow shield embankment mainly cools the permafrost under two side slopes and can significantly mitigate shady–sunny slope effect; (2) grey near-infrared reflective coating–sun/snow shield embankment can not only effectively cools the permafrost beneath the embankment but also addresses the shady–sunny slope effect; (3) these three proposed types of embankments can significantly increase the permafrost table under sunny slope by 25.25%, 72.41%, and 76.94%, under asphalt pavement by 70.85%, 65.02%, and 81.91%, and under shady slope by 41.07%, 63.40%, and 69.42%. This study contributes to the design, construction, and maintenance of permafrost embankments in Arctic regions.