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Currently, double-hole complementary ventilation is a mature ventilation method for operating tunnels, but how to carry out it in the construction tunnel poses a new challenge. Due to the desynchronization in the construction period of the double-hole tunnel, there is an instantaneous difference in the air flow demand between the two working faces. The study analyzes the impact of geometric parameters, specifically <i>L</i>_t (the distance from the traffic cross passage to the working face of the advance side tunnel), <i>L</i>_p (the distance between the pedestrian cross passage and the working face of the advance side tunnel), <i>H</i>_t (height of the upper step), and <i>L</i>_w (safe step distance of the double-hole working face) on ventilation network stability. The results show that with the increase of <i>L</i>_t and <i>L</i>_p, the <i>R</i>_m resistance of each branch changes non-uniformly, and the stability of the ventilation network is significantly different. Then, when <i>L</i>_t, <i>L</i>_p = 80 and 180 m, the air flow directions of the double-hole tunnel are the same. Finally, when <i>L</i>_t and <i>L</i>_p = 130 m, the air flow directions are inconsistent, which indicates that in the range of 80 m < <i>L</i>_t or <i>L</i>_p < 180 m, the cross-section size of the cross passage affects the stability of the ventilation network. However, when 2.5 m < <i>H</i>_t < 3 m, or 30 m < <i>L</i>_w < 50 m, the stability of the ventilation network is not affected, and the flow field of the double-holes does not interfere with each other. The conclusions obtained confirm that the double-hole complementary ventilation method is available in construction tunnels, and has potential for implementation.