Determination of optimum lenth of blast wave trap and Analysis of steel explosion-proof door in the tunnel with a blast wave trap

The purpose of this study is to investigate the effect of blast wave trap on reducing the detonation effect in tunnels and its effect on reducing the load on the explosion-proof door end of the tunnels and to analyze the types of doors in order to determine which type has the best performance against detonation. To this end, the propagation of the waves induced by the explosion of TNT-type beams with different weights is simulated in the tunnel span with a blast wave trap. The AUTODYN hydrocode is used for numerical simulations. The simulation and numerical modeling are compared and validated with analytical and empirical relationships of previous studies. Considering the maximum pressure applied to the tunnel intersection, the proper location of the blast wave trap, the optimal blast wave trap length and its effect on the maximum value of the tunnel end pressure are investigated. The output of the load applied to the end of the tunnel (location of the explosion-proof door) resulting from this time-dependent explosive load modeling is transferred to ABAQUS software to analyze and compare the types of explosion-proof doors. From the point of the load exerted on explosion-proof doors, hinged doors with different flat and arched geometries are analyzed using ABAQUS software and the maximum displacement and von-Mises stress of the doors are compared. The results show that the arch door performs better than the flat door.