Maritime vessel slamming into aerated water is a significant area of study for high-speed and lightweight craft. Upon impact with water, safety risks can lead to structural failures, endangering human life and resulting in economic losses. The design must be optimised for material usage with appropriate safety factors based on accurate knowledge of the loading and response under several impact conditions. Structural flexibility makes hydroelastic effects unavoidable, with the magnitude governed by impact type, velocity, and structure geometry. Entrained air from free-surface breaking renders the water weakly compressible, further altering the slamming dynamics. This work presents a physical foundation and experimental dataset for validating numerical models of more realistic impact conditions.

In this work, a novel experiment was set up for a combined evaluation of hydroelastic slamming in aerated water. A wedge with a 15 degree deadrise angle was designed and constructed to represent ship bow slamming. The wedge bottom consisted of interchangeable steel plates of varying stiffness. Contact and optical measurement techniques were used to capture and visualise the loading and response over the plate width. Experimental test conditions include plate thicknesses between 1 and 3 mm, impact velocities between 2 and 5 m/s and an air fraction in water between 0 and 2 %.

The results show that structural stiffness and impact velocity, captured by the hydroelasticity factor RF jointly govern the slamming response. The air fraction in water redistributes impulsive loads over time and modifies the wetted natural frequency through the influence of water density. For high-velocity impacts with significant plate deformation, as well as for impacts approaching the quasi-static regime, a lower peak strain was found for impacts in aerated water. Furthermore, for the condition where the wetting time approaches the first wetted natural period of the structure, response amplification due to hydroelastic effects was observed, with a further increase in load for the aerated water condition. This study demonstrates that aeration can amplify structural response, making it essential to take into account the physical aeration effects in the design of ship plating for slamming conditions. The structural response was found to capture the underlying physical behaviour more reliably than the pressure measurements alone. The effects of the small-scale experimental setup on the results were also identified and documented in detail.