Analysis of blast wave propgation inside tunnels

With the help of the numerical simulation finite element software LS-DYNA, a three-dimensional nonlinear dynamic simulation analysis of an explosion experiment inside the tunnel was carried out. Compared with the experiment results, the simulation results verify the availability of the material parameters adopted in the numerical simulation model. Making use of the model and the same material parameters, many results have been obtained with variety of different TNT explosion dynamites .Then the dimensional analysis was applied on the simulation results. As the explosion blast wave overpressure is the governing factor on the tunnel response, a formula was suggested for calculating the blast wave peak overpressure at a certain distance from the detonation center point inside the tunnel. Comparing the results computed by the formula with the experiment results the applicability of the formula was proved. The research is helpful to rapidly estimate the internal explosion effects on the tunnel structure.