Tsunami Impact on a Detached Breakwater: Insights from Two Numerical Models

Tsunami waves are often very energetic and therefore pose a significant threat to coastal structures. However, most defenses such as detached breakwaters designed protect against storm waves, with the consequence that tsunamis lead catastrophic failure of these This numerical study was inspired by wave scenario, which occurred at Soma Port in Japan, during 2011 Tohoku tsunami where combination tsunami-type shorter period undular bores caused severe damage caisson breakwater. The objective herein is analyze role play on breakwater stability case propagating over gentle slope into shallow water. Two complementary models, one Boussinesq type other Reynolds-averaged Navier-Stokes (RANS) volume fluid (VOF) type, used compute propagation representative composed multiple components their impact presence an bore controlled balance between nonlinearity dispersion. As draw-down from first reduces water depth around leaves structure almost completely exposed, only second transforms bore. causes breaking far offshore large amount energy dissipated ultimately resulting much less-destructive structure. influences loading breakwater, though bulk loads excessive bearing pressures were computed for long-lasting overtopping process wave. These findings facilitate assessment they relate some specific features structural mechanisms. results also provide information regarding applicability usefulness different modeling approach analysis under tsunamis. For this particular case, even depth-integrated models conclusive solutions. To best authors’ knowledge, addressing respect conditions.