Fluid structure interactions between floating debris and tsunami shelter with elastic mooring caused by run-up tsunami

Abstract

We investigated hydraulic and motion performance of a proposed tsunami shelter with an elastic mooring as space to protect people from tsunami attack and floating debris in experimental and numerical works. The results showed that the trapezoidal and streamline tsunami shelter types can reduce tsunami pressure and shelter motions such as surge, sway and heave, especially in high Froude number cases. We found that the impact pressure acting on the shelter caused by floating debris such as ship and house models can be reduced by an elastic mooring system, leading to the resultant motions of the shelter being relatively smaller and quasi-steady state. These results suggested that a tsunami shelter with an elastic mooring could be a useful option to protect life and assets during tsunami attack. Moreover, we developed a particle based model coupling with Smoothed Particle Hydrodynamics (SPH), Discrete Element Method (DEM) and Extended DEM (EDEM) with some improvements to compute fluid structure interaction among tsunami, floating debris and a tsunami shelter with an elastic mooring. We validated the proposed model with experimental results and found that the numerical results were in overall agreement for tsunami force, including collisions caused by floating debris, and shelter motions occurring due to tsunami attack. The numerical model could be a design tool for predicting fluid structure interaction between tsunami and obstacles.