Forecasting research of overpressure of explosive blast in subway tunnels

In case of an explosion happening inside the subway tunnel, blast waves interacts with the structure in an enclosed space. Both the overpressure and duration of blast increase. On the basis of experimental research, we establish a calculation model of blast effects in a tunnel. Its applicability has been verified by comparing the numerical results and the experimental findings. Then the blast effects in subway tunnel have been analyzed. It has been found out such factors as the tunnel shape, charge position, and distance to the explosion center all have a great influence on blast effects. The overpressure of blast in the subway tunnel is summarized and the formula is proposed. Compared to data of explosion tests at home and abroad, the formula has been proven to have some applicability. It may be provide some reference to the design of antiknock loads of subways and evaluation of casualties.