Study on temperature field of parallel perforated ventilation subgrade in the permafrost region

Runways in permafrost regions face significant stability challenges due to their flat geometry, wide pavement area, and pronounced heat absorption effects. To address this issue, this study proposes a novel parallel perforated ventilation system for thermal regulation. The applicability and reliability of the numerical model are validated by comparing the parallel perforated ventilation's air velocity, crushed rock layer performance, and temperature-depth profiles with existing experimental data. Key findings demonstrate that, under combined global warming and geothermal influence, the parallel perforated ventilation system maintains subgrade temperatures below 10 m depth in a frozen state for 30 years. The cooling efficacy of parallel perforated ventilation diminishes gradually with depth and time before stabilizing, with the most pronounced effect observed in the crushed rock layer, followed by silty clay, and least in strongly weathered rock. The study offers a scientific foundation for sustainable runway construction in permafrost areas, with implications for engineering practices under climate change scenarios.