Mitigating tsunami effects on buildings via novel use of discrete onshore protection systems

This study investigates the effectiveness of a new discrete V-shaped coastal barrier (V-wall) to reduce multiple tsunami-bore impacts on a group of idealized coastal structures. The performance comparison has been made between a baseline model (BM), continuous straight wall models (SW), and V-wall (VW) models. A number of key parameters including the barrier height and length along with the arrangement of the landward structures are investigated numerically using the 3-D smoothed particle hydrodynamics (SPH) approach. From the SPH models output the bore velocity, maximum force, total impulse, and pressure distribution on the structures are examined. The results indicate that the V-walls can provide a similar level of protection to continuous seawalls of the same height and hence can be considered as an economic alternative to protection in tsunami prone regions. However, in order to gain the greatest benefit from the V-walls, strategic planning of the position and orientation of landward structures and the walls themselves are needed to avoid bore flow focusing and reflection effects.