The aim of this study is to obtain the experimental data on the structural behavior of two side structures, namely standard VLCC and VLCC with additional side stringers during ship-ship collision, and to investigate the internal mechanics related with the structural deformation of struck ship. Two quasi-static collision tests was carried out on side structure models of VLCC which were composed of a double hull. Assuming the bow of striking ship as rigid, energy absorption capacity of two designs for VLCC was studied. Contribution of each structural component such as outer/inner shell plating, web frame, and side stringer etc. was discussed. Especially, the distribution of strain on the side shall plating during collision was collected in order to verify the usefulness of the numerical analysis by FEA codes.
The accident of Exxon Valdez created public sensations over the need for environmental protection, especially from the view of accidental oil spills. Since most of accidents like Exxon Valdez grounding are caused by human errors (Ohtsubo et al., 1997), it is essential to prevent the accidents themselves by reducing human errors. But, unfortunately, it is impossible to eliminate the human error perfectly. Consequently, it is very important to design the ship structure that can prevent and/or minimize the oil outflow even though the accidents have occurred. Following the Exxon Valdez grounding in 1989, several big projects on the collision and grounding of tankers have been carried out, and new regulations such as Oil Pollution Act of 1990 (OPA90) were issued by the US government and IMO (Ohtsubo et al., 1994). The OPA90 requires that all oil tankers operating in US waters must have double hulls by the year 2015.
