Integrative heat-dissipating structure for cooling permafrost embankment

In Qinghai-Tibet Plateau, the construction of asphalt pavement is one of main reasons for permafrost thawing. To decrease the heat accumulation in permafrost embankment, a new route is proposed by inducing a highly oriented heat conduction in asphalt pavement and accelerating a convective heat release from crushed-rock embankment. On this base, two integrative heat-dissipating structures, named G-IHDS (combination of oriented heat conduction structure and crushed-rock embankment) and R + G-IHDS (combination of heat reflective layer, oriented heat conduction structure and crushed–rock embankment), are designed. The results show that the net annual heat accumulation in an embankment decreases by 16.7% for the G-IHDS and 34.9% for the R + G-IHDS, which results in a temperature reduction in the embankment. For example, the summertime mean temperature on the top of the embankment reduces by 0.66 °C for the G-IHDS and 1.58 °C for the R + G-IHDS. The cooling effect of the G-IHDS is validated against an indoor irradiation test. It can be concluded that the permafrost embankment is expected to be cooled by controlling an integrative heat dissipation in asphalt pavement and a crushed-rock embankment.