Deformation of Fixed Support Steel Plate under Explosion Load in Negative Pressure Environment

In order to study the dynamic response of the structure under explosion load in negative pressure environment, the negative pressure explosion experiments were carried out for the fixed supported steel plate, which is as a simplified unit of the protection project. The deformation law, and the ultimate strain and failure conditions of the fixed supported steel plate under different negative pressures were analyzed. The numerical simulation of the dynamic response of the fixed supported steel plate under negative pressure explosion load was carried out by AUTODYN, and the accuracy of the numerical simulation results was verified by comparing the experimental results. The results show that when the initial ambient pressure decreases, for the same burst distance, both the maximum deflection and the maximum velocity at the center point of the steel plate decrease. Under the negative pressure explosion load, the steel plate produces large plastic deformation, the oncoming surface forms a pit, and obvious tensile deformation occurs at the edges perpendicular to the boundary direction. The deflection changes in the edge zone are basically the same, and the maximum deflection at the center point decreases with the decrease of environment pressure. Through the bidirectional strain assumption, the dynamic limit strain of the steel plate is determined to be 0.269. The reflectance specific impulse formula of explosive blast wave under negative pressure environment was established, and the failure criterion based on rigid-plastic hypothesis and energy criterion were examined. The research results can provide a reference for the equivalent evaluation of the shock wave power of explosive air in negative pressure environment and the target damage assessment in plateau environment.