2019 Volume 75 Issue 2 Pages I_913-I_918
A hydro-plane type movable breakwater has been developed, which lie on sea bottom in still water but is raised by Tsunami actions without any man operations and electric power. It is required that the breakwater against Tsunami has “redundancy and robustness”. It means that even if the breakwater is partially failed, it should carry further load and continue to reduce Tsunami effect. In order to assess such kind of “redundancy and robustness”, collapse behavior of the breakwater should be investigated under extreme load beyond design load.
In the present study, the static collapse behavior of the hydro-plane type breakwater is simulated by using nonlinear finite element method (FEM) and ultimate strength of global and local structures is assessed. The ratio of the global ultimate strength to the local one may be regarded as one of the indexes to assess “redundancy and robustness” of the breakwater. In addition, based on the knowledge regarding the collapse behavior of the breakwater obtained from the FE analysis, a simplified method to estimate the global ultimate strength of the breakwater is developed, in which the ultimate strength is predicted based on initial yield criteria while considering reduction of effective width of plate panels due to buckling. The proposed method gives a 15% safe-side prediction of ultimate strength compared to the result of FEM.
PROCEEDINGS OF COASTAL ENGINEERING, JSCE
PROCEEDINGS OF THE JAPANESE CONFERENCE ON COASTAL ENGINEERING
