A STUDY ON DAMAGE REDUCTION MEASURES FOCUSING ON RUBBLE MOUND DURING CONSTRUCTION

Abstract

 When high waves caused by the typhoon act on the rubble dike during construction, the rubble mound could be damaged. That is one of serious problems in the field. Therefore, it is necessary to propose countermeasures to reduce the damages of the rubble mound during construction. From the investigation of the damage area, the submerged depth of mound was deformed to about 1.2 times the significant wave height of the incident wave. The net was installed inside the area as a measure to reduce damages, and both ends were held with stone baskets. The net was made of fiber and wire mesh with different flexibility, but there was no difference in effect depending on the material. The amount of stones flowing out of the design section was evaluated as the damage rate. As a result, the amount of stones flowing out was reduced to less than 1/2. The proposed measures to reduce the damages have obtained good results. Applicability to the field can be sufficiently achieved by selecting a net with high durability. This method could be expected to be applied to the field.