A new type of tsunami generator, forty-five meters long and four meters wide, has been developed in the University’s Ujikawa Open Laboratory of the Disaster Prevention Research Institute. The generator is composed of a piston-based wave maker with a long stroke, a current generator, and an overhead water tank. The combination of waves generated by this apparatus is capable of reproducing any type of tsunami wave. The current generator, in particular, is needed to produce the long period tsunami profiles that follow initial bore-type waves. The water tank, meanwhile, can not only produce tsunami caused by volcanic eruptions, but also by a spike in the bore. This versatility makes this generator the only one of its kind in the world.
The apparatus is currently being used to investigate the effectiveness of removable breakwaters, and as its next project, tsunami pressure distribution around buildings located in high-impact zones. The experimental results will be applicable to studies of tsunami hazard characteristics, and in verification of numerical simulation models. The generator’s contributions are eventually expected to reduce hazard levels and increase coastal front resilience.

Tetsuya Hiraishi, PhD

Professor, the Research Center for Fluvial and Coastal Disasters, Disaster Prevention Research Institute