Abstract: In order to explore the influencing factors of cable fire spread in the comprehensive pipe gallery, the cable cabin in the L?shaped utility tunnel was numerically simulated to study the cable fire spread speed and temperature change in the utility tunnel under different wind speeds and single/double side fires. It is found that the increase of longitudinal ventilation wind speed and bilateral fires promote the spread speed of cable fire in the utility tunnel. When the utility tunnel is on fire on one side and the longitudinal ventilation wind speed is no more than 0.2 m/s, the flame combustion will be promoted, thus increasing the internal temperature of the utility tunnel. When the longitudinal ventilation wind speed is more than 0.2 m/s, the cold air brought from outside will cool the internal temperature of the utility tunnel; When there is a fire on both sides of the utility tunnel, the impact limit of wind speed on the internal temperature of the utility tunnel changes from 0.2 m/s to 0.4 m/s, that is, when the wind speed is no more than 0.4 m/s, the temperature in the pipe gallery will be increased; when the wind speed is more than 0.4 m/s, the temperature in the utility tunnel will be reduced.

Key words: utility tunnel, cable fire, wind speed, fire on both sides, spreading speed