A construction method of huge offshore structures has been conceived ; that is, several unit structures constructed on land are assembled and jointed on sea. The method has such advantages that conventional docks can be utilized and the construction period can be reduced. However, as this method obliges the work on sea to be carried out under the environmental influence of wave, wind and current, the investigation of the influence, especially the wave induced vertical bending moment of a joint part is important at the design stage.
This paper presents a calculation method which gives the motions and wave loads at a joint part of a floating body assembled from two unit bodies. The hydrodynamic forces can be derived from solving the boundary value problem of two bodies floating in regular waves by means of a 3-D singularity distribution method.
The equations of the motions including wave loads as unknown external forces and moments of the two unit bodies are solved by using the conditions at the joint part.
From good agreement between the results of the calculation and model tests, it is confirmed that the introduced calculation method is effective.