Based on the model of the designed sections of Gonghe-Yushu high-grade road

the cooling effect of the inclined thermosyphon embankment and the inclined thermosyphon-XPS insulated board embankment were analyzed by numerical simulation.The results show that both of the two embankments could cool down the permafrost temperature and raise the permafrost tables in the specified period under the background of global warming.However

with the air temperature rising

the melt bubbles would appear in the permafrost under the loading berms of the two embankments

the inclined thermosyphon embankment

and in the filling of the inclined thermosyphon-XPS insulated board embankment.Increase of the XPS insulated board could enhance the cooling ability of the inclined thermosyphon embankment in a given period

and make the cooling effect of the inclined thermosyphon-XPS insulated board embankment better than that of the inclined thermosyphon embankment.The permafrost table of the former is higher than that of the latter

but the long-term cooling effect of the inclined thermosyphon embankment is not remarkable for the XPS insulated board.