Evolution characteristics of monthly average temperature ofsubway stations with operation years

This paper establishes the theoretical model of air heat balance in subway stations. Based on the air temperature of the interval tunnel and the heat storage and release of the soil surrounding the subway station, the annual evolution characteristics of the monthly average temperature of subway stations at the initial, middle and long stages of operation are obtained. The study results show that with the increase of the operation years of the subway station, the monthly average temperature shows an upward trend year by year. In the 15th year of operation, compared with the first year, the monthly average temperature of the station has a minimum rise of 3.1 ℃ in January and a maximum rise of 10.6 ℃ in August. Under the existing operation mode of the subway train density increasing with the operation years, the initial train density of the subway station is only 15 pairs per hour, and the highest air temperature of the station in summer is 26.4 ℃ in the 5th year, which is much lower than the average air conditioning design temperature of 29 ℃ in the station hall and platform in summer. So the cooling capacity provided by the station air conditioning system is much larger than the cooling load demand of the station at the initial stage of operation, and there is a certain energy-saving potential in the station air conditioning system.