Mechanism and efficiency of a hollow polycarbonate panel heating method on impervious soil of dams in cold regions

Abstract

During the construction of earth−rock dams in cold regions, the freezing−thawing of impervious soil causes significant changes in its physical and mechanical properties, which affects the quality and operation safety of the project. To enhance the impervious soil anti−freezing capacity, the hollow polycarbonate panel heating method (HPPHM) was innovatively proposed. Based on the mechanism and in−situ tests, the heating mechanism and effect of HPPHM on impervious soil were investigated. The test results indicated that HPPHM can primarily heat the soil through solar radiation, raising the soil temperature. Furthermore, the air layer inside the panel serves as thermal insulation, effectively preventing the soil internal heat from dissipating. The in−situ test results showed that soil freezing was not observed under HPPHM, and the soil surface temperature was approximately 6 °C higher compared to the control site. The heating influence depth of HPPHM on the impervious soil was approximately 175 cm. Additionally, the soil heat under HPPHM experienced a significant increase of 12537.1 kJ. This study provides a scientific method for improving construction efficiency and quality in cold regions.