Field test study on thermal performance of a novel embankment using solar refrigeration technology

The embankment construction in permafrost regions affects the energy exchange process between the original ground and the surrounding environment, accelerates the degradation of the underlying permafrost layer, and endangers the stability of the embankment. To prevent permafrost degradation, a solar air conditioning system based on solar refrigeration technology was proposed. In this study, a field test of cooling embankment was carried out in permafrost regions, and the cooling performance of the new technology was analyzed. The solar air conditioning system shows good cooling performance, with a horizontal influence range of about 1.77–2.28 m and a vertical influence depth of more than 3 m. By active cooling, the temperature of the permafrost layer beneath the embankment decreased significantly, and the permafrost table rose by about 0.3 m. In addition, the influence mechanism of complex environmental factors on the cooling performance of the solar air conditioning system was revealed by correlation analysis and machine learning methods. Compared with existing technologies, solar refrigeration technology achieves active refrigeration during the whole season and presents a significant price advantage. The research results help promote the application of solar refrigeration technology in transportation geotechnics and provide a new approach for actively cooling embankments.