Abstract
The importance of breakwater stability for giant tsunami has been increasing since 2011 East Japan Disaster. Miyazaki Prefecture, located in south-east of Kyusyu Island has also major potential of large tsunami induced by Nankai trough earthquake. This study aims at studying countermeasures for resilient breakwater against tsunami and clarifying the effects by conducting the physical model test.
The examination of armor block stability with the hydraulic experiments clarified that consideration of slope angle in the Isbash formula can overestimate the minimum weight of armor blocks. The results of the physical model tests revealed the effects of friction-increasing asphalt mat to the stability of armor blocks. The paper concluded that the optimum countermeasure in the breakwaters are to set 8 tons blocks on the rubble mounds with cost comparison of countermeasures.
