Abstract
The experimental studies on the measurements of the impact pressure and the transitional bending strain of the circular plate produced by falling water mass impinged on the surface of the plate are carried out as the fundamental investigation obtaining the information to the analysis into the local damages of deck or house wall due to a clean breach on rough waves. The apparatus for the falling mass of water made on experiment in our laboratory is employed and the several test specimens of the circular plate with different natural frequencies are prepared. Both the impact pressure and the transitional bending strain of the plate due to impinging water mass are recorded on an oscillogram with common timing. With regard to the pressure-time curve, the shape is divided into two parts, one is the gifle part the other is the bourrage part. It is a matter of course that the pressure of the gifle part affects conspicuously upon the transitional amplitude of the test plate. As the result of the tests, the maximum dynamical bending stress of the plate produced by the impinging water mass was obtained 1.6〜1.7 times of the statical one when the impact duration of the gifle part takes 1.5〜1.7 times of a half period of the natural vibration of the circular plate in the present experiments.
