Wave Response Analysis of a Sinkable Float-type Storm Surge Barrier Through Hydraulic Experiments

Abstract

A sinkable float-type storm surge barrier is a new type of structure, which can reduce coastal disasters due to storm surges. This barrier usually rests on the seabed and uses its buoyancy to rise up and form a seawall when a storm surge occurs. Sinkable float-type storm surge barriers consist of a buoyant main body connected to a foundation structure on the seabed by a hinge. In this study, a wave response analysis is experimentally conducted on the barrier. In order to examine the wave reflection and transmission of buoyant float-type storm surge barriers, hydraulic experiments were conducted at 1/10th scale under regular and irregular wave conditions with free and semi-free movement. The wave blocking capabilities of the sinkable float-type barrier against storm surges were confirmed. In addition, the characteristics of the barrier motion and wave pressure have been clarified with changing wave conditions. Two types of barrier, free-moving and semi-free-moving, were tested. From the hydraulic experiments, it was found that this type of barrier is effective to the wave transmission as well as reflection. Furthermore, it was shown that the semi-free-moving barrier cases are more effective to the wave blocking. It is shown that a sinkable float-type barrier placed at the mouth of a bay can be used as a storm surge barrier. However, further detailed hydraulic and numerical experiments are needed to calculate accurate predictions of barrier motion under wave-current combined conditions.