Physical Modeling of Horizontal and Vertical Tsunami Forces on the Elevated Overland Structure

Abstract

In this study, two-dimensional hydraulic model tests were conducted to investigate the characteristics of the force of tsunami waves on the simplified box-type elevated structure. The vertical elevation of the structure was changed to investigate the relation between the wave force and the air gap. The tsunami waves were generated by using the error function with the full-stroke of the wave paddle to maximize inundation. The horizontal and vertical wave forces and pressures on the structure by the tsunami waves were measured, and the relation between the maximum wave force, air gap and the incident wave condition was derived. Using the measured maximum horizontal wave force from the different wave conditions, the empirical formula of the non-dimensionalized horizontal wave force as a function of the surf similarity parameter was obtained. It was found that the horizontal wave force is inversely proportional to the surf similarity parameter in the case of the unelevated structure. The experimental results also showed that the ratio of the horizontal force to the vertical force is larger in the case of broken and breaking wave conditions in the case of the elevated structures.