Abstract:Combining the collected data and numerical simulation,the main influential factors on ventilated embankment are analyzed in the light of heat transfer in permafrost engineering. It is found that there is a strong heat flux between the two adjacent ventilating pipes in the ventilated embankment;and the distance between the two adjacent pipes is one of the important factors influencing the cooling effects. This is proved by measured data. According to the measured data in Beiluhe test site along Qihai—Tibet Railway in Qihai—Tibet Plateau,in ventilated embankment testing field,the cooling effect with vent-pipe diameter 30 and 60 cm between the two adjacent pipes is better than that with diameter 40 and distance 80 cm. Because of the strong heat-absorbing action of black asphalt road,the numerical simulation shows that the heat flux between the ventilating pipes is much larger than that in the road with sand-soil surface;and the cooling effect of the ventilated embankment will be weakened,it can become invalid if the design is improper. With this situation,a creative method is suggested to enhance the embankment design. The numerical simulation of this “new style” embankment demonstrates its efficacy and quickness in cooling embankment. Three years after the development and application of this “new-style” embankment with an asphalt surface,the ground temperature at 3 m under center of embankment bottom surface appeared to be lower than that in the natural condition;and the entire permafrost table remains solid during the intended road¢s service duration. The permafrost table quickly rises to 0.5 m under the embankment bottom. It effectively solves the asymmetry problem in the embankment thermal field. This can be also helpful in maintenance of the long-term stability of the embankment. These results have significant effects on highway design in permafrost regions.