1:45 PM - 3:15 PM
[O07-P56] Development of variable slope type underwater embankment
Keywords:tsunami, Underwater embankment
We conducted research on variable slope type underwater embankment with the aim of developing underwater embankment that have a higher energy-reducing effect on tsunamis than conventional types. The research was conducted by combining a demonstration experiment in a laboratory using a small model and a computer simulation. In the demonstration experiment, waveforms were collected using an ultrasonic sensor, and the effect of the variable slope type underwater embankment was verified as compared with the case where a normal fixed underwater embankment was installed and where there was no underwater embankment. In addition, in the demonstration experiment, by using BB bullets as a tracer, the distance traveled by the waves of water molecules was estimated, and the changes in the amount of energy possessed by the waves were also compared. In the simulation, two-dimensional physics software, Algodoo, was used, and the accuracy of the demonstration experiment was verified using the discrete element method by reproducing the environment of the demonstration experiment. As a result of the experiment, it was found that the energy of the waves passing through the variable slope type underwater embankment tended to be dispersed over a wide area. In addition, the total amount of energy possessed by waves decreased the most when the conventional fixed underwater breakwater was installed. From these facts, the variable slope type underwater embankment reduces the load on the embankment compared to the conventional breakwater and disperses the wave energy over a wide area to reduce the amount of energy that rushes to the ground in a certain period of time, and the breakwater on the ground collapses. Ultimately, we would like to connect not only the variable slope type but also the curved underwater embankment whose shape itself changes.