Research on the ventilation and control method of double-hole complementary construction of long tunnel

The realization of two-bore complementary ventilation in construction tunnels is a new challenge. This paper takes two-way four-lane, six-lane and eight-lane tunnel as the research object, and studies the possibility of two-bore complementary construction ventilation and the influence of construction parameters on the effect of complementary ventilation when when there is a difference in wind demand of double-bore. The results show that: two-bore six-lane tunnel is in line with the characteristics of the complementary construction ventilation, when the distance from the wind pipe outlet to the working surface is 20 m, the height of the upper step is 3.5 m, and the safety distance between the working face of the twin holes is 50 m, the ventilation effect of double-hole complementary construction is enhanced. This kind of ventilation can introduce the surplus airflow from the tunnel with small air demand to the tunnel with large air demand, reduce the energy consumption of the tunnel ventilator in the tunnel with large air demand, and enrich the theory of the tunnel construction of the long double-cavity construction.