Study on a Simplified Method of Tsunami Risk Assessment

For the testing of the effect on the tsunami prevention facilities, a simplified method for tsunami risk assessment was suggested without wave run-up analysis. This method is proposed using calculated offshore tsunami waveform and field reconnaissance such as the seawall height, time necessary for residents’ evacuation and tsunami warning insurance. Then, two normalized values are evaluated; one is the ratio of calculated maximum tsunami height to seawall height, the other is the ratio of time between tsunami over-topping and evacuation completion to total time required for evacuation. These two values are used to qualitatively estimate the safety of residents and the effect of tsunami prevention facilities, eliminating the necessity to compute complicated tsunami run-up onshore.