Abstract
This paper discusses the hydrodynamic tsunami-induced force acting on a bridge superstructure based on hydraulic model experiments and numerical simulations. Hydraulic experiments were conducted with using models of box girder bridge to clarify the influence of tsunami wave shapes to tsunami wave forces acting on it. Experimental results showed that tsunami wave forces were different according to the shape of tsunami incident wave, even if the maximum tsunami height and the tsunami velocity were the same and it was confirmed that maximum wave forces could be expressed as a function of the wave front slope of tsunami incident wave. Furthermore, the numerical simulations were conducted to reproduce the results of the hydraulic model experiments. As a result of simulations, it was found that while wave forces when a tsunami collided to a bridge girder corresponded with the experimental results by a twodimensional simulation, in order to evaluate wave forces when a bride girder was submerged, it was necessary to reproduce the three-dimensional structure of vortex around the cross-section by a three-dimensional simulation.
