## 3 Experimental Results for Model with Deadrise Angle of 10\({}^{\circ}\) and Cylindrical Model  
It seems that the second peak pressure occurs when the negative pressure, due to the elastic effect, was close to \(-\)0.1 Mpa.  
Figures 9 and 10 show that the second peak was larger than the first peak in the wedge models. However, in the case of the cylinder models, except for the bottom thickness of 3 mm, which is largely deformed, the size of the second peak was smaller compared to the first peak.  
As the bottom thickness increases, the pressure tends to increase. In the case of the bottom thickness of 3 mm, in which deformation occurs, the pressure history shows that the fluctuation of the shape of the pressure was very large and it persists. In the case of slamming loads, the peak pressure and the duration of it are important factors. Longer durations along with peak pressures indicate longer and high loads on the structure.  
Figure 10: \(Cont.\)  
Figure 9: History of pressure and strain in the model with deadrise angle of 10\({}^{\circ}\) (Drop height: 1.0 m).  
Figures 11 and 12 show that the strain history does not converge to zero, when the impact was applied and deformation occurs, the second peak due to the elastic effect was confirmed to be larger or similar to the first peak.  
Figure 11: History of pressure and strain in the model with cylindrical shape (Drop height: 1.0 m).  
Figure 10: History of pressure and strain in the model with deadrise angle of 10\({}^{\circ}\) (Drop height: 1.7 m).  
It seems that the negative pressure occurred due to the elastic influence of the structure. Figure 13 shows that the negative pressure of the rigid model, made of wood, was negligible. On the other hand, in the case of the elastic model, made of steel, negative pressure was confirmed, as shown in Figures 11 and 12.  
As shown in Figure 14, when the bottom thickness was 3 mm, deformation occurred at both 1.0 and 1.7 m drop heights. Figure 14 shows the strain measured after repeated drop tests. At the  
Figure 12: History of pressure and strain in the cylindrical model (Drop height: 1.7 m).  
Figure 13: History of pressure in the wooden wedge model with a deadrise angle of 0\({}^{\circ}\) and 10\({}^{\circ}\) (Drop height: 1.7 m).  
bottom thickness of 8 mm, no deformation occurred, so it is omitted. The deformations for the models with bottom thicknesses of 5 and 3 mm were measured and plotted. The deformation was measured by measuring the center cross section of the model, and each deformation is shown in Figure 14. Deformation did not occur when the bottom thickness was 5 mm and the drop height was 1.0 m, and deformation occurred when the height was 1.7 m. The deformation was measured by performing five-time free drops, and the maximum deformation of the central section was up to 140 mm. The model with a bottom thickness of 3 mm was deformed at both 1.0 and 1.7 m. Deformation was measured twice at the drop height of 1.0 m, and the maximum deformation of the central cross section occurred up to 140 mm. Due to the high degree of deformation of the model, no additional drop test was possible. At 1.7 m drop height, the maximum deformation of the central section was measured to be more than 150 mm. The model was so deformed that further drop tests were not possible.