Slamming Response and Structural Failure of a Small Cargo Vessel (2nd Report)

In the first report, it is clarified that a small cargo ship of length 48m in ballast condition is subjected to large hogging moment due to bottom slamming. In this report, the strength of the ship at S. S. 7 against hogging moment is estimated with the help of experiments for a structural component. The collapsing strength of S. S. 7 is significantly reduced by the existence of bottom corrugations which may be caused by slamming previously. Bottom corrugations reduce the effective stiffness of the bottom plates and also the section modulus I/y for bottom. Compared with the value of hogging moment caused by slamming, the strength of the ship may be insufficient for preventing the structural failure of the ship, although it is much larger than the required strength against the bending moment expected by the linear conventional theory.