2024A-GS14-1 Tsunami Protection Performance of Floating Tsunami Mooring Bitts for Vessel Moored at Wharf Against Backwash

Abstract

Moored vessels in ports face significant risks from tsunamis, necessitating the implementation of robust tsunami disaster prevention and mitigation strategies. Our preceding research introduced floating tsunami mooring bitts (FTMB) as an innovative mooring facility designed for vessels at wharves, specifically targeting tsunami disaster protection. This facility exhibited exceptional performance in mitigating the impact of a tsunami's leading wave. In the current study, we extend this research to assess the FTMB's effectiveness in protecting moored vessels from tsunami backwash, employing the three-dimensional moving particle simulation (MPS) method. We analyzed three FTMB variants: the pillar type, the slit type, and a hybrid combination of pillar and wall structures. The simulations also included an evaluation of the combined effect of these FTMB types and enhanced mooring forces, achieved using high-performance fiber lines. Our findings indicate that optimal protection against tsunami backwash involves strategically positioning the FTMB to reduce horizontal flow velocity impacting the vessel, coupled with reinforced mooring forces.