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Snow removal is a critical security issue in airports, where heat-pipe technology can be an environmentally friendly and efficient alternative to traditional approaches for snow removal. This study investigated the long-term thermal regime of airfield-runways equipped with a heat-pipe system, using data collected over several recent years from two full-scale snow-melting systems, one located in Beijing, and the other in Harbin, China. The findings showed that the heat-pipe system automatically increases the airfield-runway surface temperatures by up to 17 °C utilizing geothermal energy in winter for preventing icing. Surface temperature levels up to 0 °C were observed to increase by over 25% when a shallow pipe embedded depth and a longer pipe evaporation section were selected. However, the surface temperature was less affected by the diameter of the heat-pipe. Field experiments indicated that, the heat-pipe technology threshold value for the airfield-runway snow-melting performance was an ambient air temperature exceeding −10 °C. Using the heat-pipe technology, the snow-melting rate on an airfield-runway was about 3–8 mm/h within the working range, and there was therefore a decrease in the snow-cover durations. Particularly, the heat-pipe airfield-runway was always free of snow when the average ambient air temperature exceeded −4 °C. The statistical results illustrated that the heat-pipe airfield-runway snow-melting system is applicable in more than 78% of the cities in China, indicating that this technology is feasible and practical in China and can be applied in other countries.

Application of gravel pile is a common foundation treatment method in civil engineering infrastructure constructions. The main purpose is to improve the foundation bearing capacity, reduce deformation and enhance the resistance to liquefaction. However, there are some problems in the traditional monitoring methods of gravel piles, such as irregular construction operation, unreliable process control, unscientific quality assessment and other issues. To meet the higher requirements of the construction quality monitoring for gravel piles, this paper researches and implements a construction quality monitoring system for gravel piles based on the Internet of Things technology, which is based on the analysis of control parameters for the construction quality of gravel piles. Field test results show that the system hardware has good earthquake resistance, data integrity, real-time performance and high reliability, with centimeter-level monitoring accuracy for pile point location and