A Study of Unsteady Variations of Highway Temperatures in Winter and Summer

Abstract

The unsteady variations of temperatures of highways in four places are investigated in this study. A physical model is built based on heat transfer, and the computer program for the analysis is generated by authors in Fortran code. The effects of solar radiation, air temperature, wind velocity and location on highway temperature are analyzed. The results show that the highest temperature on the highway surface could be over 60 ºC in summer, and the lowest temperature could be below -14 ºC in winter. The solar radiation, air temperature, location and wind velocity affect the road temperature obviously. Due to the thermal inertia, with the increase in depth, the temperature changes more slowly and weakly. At the depth of about 0.5 m below surface, the variation of road temperature is not over 1 ºC. The structure and the altitude above sea level of the highway also play important roles in influencing road temperature. The frozen depths for the researched highways could reach 0.25 m~0.95 m.