To study the loading characteristics of shock wave along the water surface in near-surface explosion scenarios, explosion tests were carried out with three typical scaled height of burst . The explosion tests were contact burst (H_ = 0), near-surface blast (H_ ≈ 0.2m /kg1/3) and air blast (H_ ≈ 0.6m /kg1/3). In the experiment, 100 g, 200 g and 400 g TNT/RDX(40/60) explosives were used, and the shock wave overpressure and high-speed photographic images of the explosion were measured. Meanwhile, numerical simulation method is used to simulate the experiment. Based on the experimental and numerical simulation results, the explosion phenomena and the characteristics of shock wave loading on water surface were studied. The results show that there are significant differences in the explosion phenomena of contact burst, near-surface blast, and air blast. In contact burst, the detonation products directly drive the water surface to form a hemispherical cavity, and the water on the edge of the cavity is squeezed upwards to form a hollow water column. In near-surface blast, the collision of the detonation products with the water surface is relatively weak, and the shock wave on the water surface mainly propagates outwards as Mach waves along the water surface. In air blast, there are obvious regular and irregular reflection zones of the shock wave on the water surface. The shock wave overpressure on water surface of contact burst is lower than that of near-surface blast, therefore, the water surface cannot be considered as a rigid plane in contact burst. The underwater shock wave pressure of contact burst is higher than that of near-surface blast. The formulas of overpressure and positive pressure duration of shock wave on water surface within the range of 0.5~4.0 m/kg1/3 in contact burst and near-surface blast were obtained through data fitting, which can provide reference for shock wave loading calculation and analysis.
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