EFFICIENT LONG-PERIOD WAVE ABSORBING SUBMERGED MOUND STRUCTURE

[摘要] In many Japanese ports, it has been reported that long-period waves with periods of 30 to 200s cause serious problems in cargo handling. As a countermeasure, wave absorbing mounds installed on the harbor side of breakwaters have been constructed. The crown heights of such rubble mounds are almost equal to those of the caissons. Although such structures can be expected to provide some wave absorbing performance, they are too large to apply to specific site conditions. It is important therefore to reduce the size of the structure to apply to specific site conditions. In our study, a slightly submerged mound type long-period wave absorbing structure is proposed. A series of hydraulic model experiments was carried out to evaluate the wave absorbing performance in port and stability characteristics of the armor units against wave overtopping from the sea side. Throughout this study, it became clear that submerged structures display a higher wave absorbing performance compared with those of conventional structures. Moreover, a prediction formula for the stability number for Tetrapods covering these submerged mounds is proposed.

[学科分类] 建筑学

[关键词] lightly submerged wave absorbing mound;long-period wave;hydraulic model experiments