Hydro-Elastic Criterion for Practical Design

A new hydro-elastic criterion which can be used inpractical design of marine structures is proposed in thispaper. By application of this criterion a designer will beable to decide whether a hydro-elastic problem can stillbe addressed by the standard two-step practice wherebyin the first step the hydrodynamic load is determined ona rigid model of the structure and in the second step theaccompanying structural response is calculated.
The criterion has been developed based on nondimensionalnumerical calculations using a simplelumped-mass model of a flexible cone impacting thefree water surface. The penetration velocity is hereby 'in contrast to the assumptions so far in previous investigations' not prescribed, but results from the numericalmodel.
In addition the paper will demonstrate that the standardtwo step practice does not essentially lead to conservativeresults toward the response of the structure.Based on the findings of this paper the research is continuedat MARIN and experimental validation is underway.