Determination of Wave Loads for Ship Structural Analysis

The adequacy of a structure can only be realistically determined if it is assessed with sound knowledge of the loads that are likely to be applied to that structure. Therefore, methods for evaluating hydrodynamic loads on ships have been reviewed in order to assess their applicability to RAN ships. The different methods are used at various stages of design or analysis dependant upon the amount of time and information available to the designer/analysist. Methods for calculating still water loads and wave bending loads using the Static-Balance method are outlined and comparisions of the methods provided. The use of Strip Theory methods to determine the probable and design extreme amplitude shear force or bending for a particular sea state is explained and predictions are compared with full scale measurements. Methods for long term load predictions such as Adamchak's Method and load shortening curves are also discussed. Methods for applications of these loads to finite element models are given and the particular case of an analysis of an RAN ship is discussed