Dynamic mechanical characteristics and anti-thaw measures of warm frozen soil

• The research progress of warm frozen soil dynamics was discussed. • The application method of all-season refrigeration technology in permafrost embankment was put forward. Permafrost is widely distributed across the Qinghai-Tibet Plateau, and under the influence of climate warming, low-temperature frozen soil is gradually degrading into warm frozen soil. The ratio of ice to unfrozen water in warm frozen soil is highly sensitive to temperature changes, resulting in significant instability in its mechanical properties. To ensure the long-term stability of structures overlying permafrost foundations, conducting research on the mechanical characteristics of warm frozen soil and proposing effective measures to mitigate thaw settlement are crucial. This paper presents the research progress of our team in the field of warm frozen soil dynamics. Using a dynamic triaxial apparatus for frozen soil and a self-developed dynamic direct shear apparatus, we investigated the behavior of warm frozen soil under different temperatures, revealing the influence of temperature on its dynamic stress-strain relationship and dynamic parameters. The development of frozen soil creep theory is reviewed, and advancements in frozen soil dynamics research are summarized and discussed. This paper proposes the use of solar refrigeration technology to protect permafrost, introducing a solar-powered compression refrigeration device and its working principles. The active cooling performance of the device was tested through model experiments and field trials. Additionally, the design and construction techniques of all-season cooling embankments are discussed, providing theoretical and technical support for the stability control of subgrade engineering in permafrost regions.