Comparative study on damage effects of penetration and explosion modes on airport runway

As an important part of civil and military buildings, airport runway is an important research object in the field of protection. In this study, damage assessment of scaled-down target of airport runway was carried out through experiment and numerical simulation. Two experimental methods, static explosion of charge after penetration and explosion of prefabricated hole, were used to damage the target and crater size and surface acceleration of the target were measured and analyzed. The experiment proves that the damage effects of the two methods were obviously different. The crater size produced by static explosion of charge after penetration was obviously larger than that produced by explosion of prefabricated hole under the same explosion depth and explosive charge, of which the shapes were also different. The numerical calculation model was established, and static explosion of charge after penetration was realized and detonation products leakage in inward explosion were solved through restart and S-ALE numerical calculation methods. Calculation results were compared with the experimental results; state equation and parameters were verified; damage effect diagram was obtained by numerical calculation, and mechanism of damage difference was analyzed. The study noted that obvious difference in explosion pressure transmitting and structural failure modes in multi-layer medium and that in a single medium. It proved that the damage caused by penetration will affect cratering effect and the movement of detonation products. Based on the experimental and numerical results, two formulas were given for calculating the crater sizes of airport runway under static explosion of charge after penetration and under explosion of prefabricated hole. The effect of dimensionless penetration coefficient and dimensionless explosion coefficient on crater size was determined by analyzing the crater relation curve of airport runway. The study indicates that the size difference between static explosion of charge after penetration and explosion of prefabricated hole charge can reach 30%. To carry out more accurate study on the damage of the projectile to target, the experiment should adopt static explosion of charge after penetration.