Reflection of Charge Explosion Shock Wave from Concrete Floor

In order to further investigate the reflection characteristics of shock wave from a concrete floor after charge explosion, the propagation characteristics of shock waves at the air-concrete interface are analyzed by introducing the medium-related attenuation coefficient β based on the theory of shock wave propagation during charge explosion and the theory of shock wave propagation at the interfaces of different media. The reflected overpressures at different distances on the concrete floor are characterized by using the coefficient β obtained through analysis, and a finite element model of charge explosion is established. The reflection characteristics of concrete floor are studied through numerical simulation, and the propagation process of shock wave is analyzed to get the values of the reflected overpressures at different distances. In the experimental research, the reflected overpressures of concrete floor after 80 kg TNT charge explosion is measured to obtain the reflected overpressure at the measuring point at a horizontal distance of 5 - 20 m from the explosion center. The results show that the reflected overpressure decreases with the increase in the distance. Based on the test values, a fitting formula for proportional distance-overpressure was obtained. The measured values of reflected overpressure are quite close to those characterized by β. Therefore the calculation method of characterizing the reflected overpressure of concrete floor by the attenuation coefficient β can provide a certain reference for the study of the reflective properties of concrete floors.