Added Mass Depending on Vibration Modal Shape in Floating Artificial Base

The floating structure of pontoon type, for example Mega-Float, can be expected to use as a supporting structure, it is called “floating artificial base”. A building can be built on the surface of that base. Many studies with regard to the floating artificial base have been carried out. Consequently, it was concluded that the large floating artificial base had to be analyzed by elastic behavior problem. It is essential for dynamic analysis of floating structure to estimate fluid influence. Therefore, we have been studying the added mass evaluation relating as coupled vibration analysis between fluid and structure. It was assumed that this floating artificial base was a plate structural system. In order to propose added mass depending on vibration modal shape for natural frequency analysis and for wave response analysis, the study has been approached by way of experiment and theoretical approach. A simple equation for calculation of the added mass could be proposed through the study of the characteristics of added mass distribution. This simple equation was introduced in the last OMAE conference. That equation showed well in agreement with the experimental result and the other published data. We have been continuing to examine its validity by comparison with data obtained through the systematic experiments using different testing plate models, and also the comparison was done with the measured data from the existing floating structures. This paper reports the evaluation of present simple equation from a serious of research work.