3. Procedure for the development of residual strength – damage index diagram
The general procedure for the development of an R–D diagram is shown in Fig. 2 (Paik et al., 2012). Once a ship’s structural characteristics have been defined, including its geometry, dimensions, and material properties, a limited number of probable damage scenarios representing all possible scenarios can be selected by a probabilistic approach.
Each parameter affecting the structural damage is dealt with as a random variable and it shall be characterized probabilistically. In the present paper, the probability density distributions for the grounding damage parameters defined by IMO (2003) are applied. Also, due to computational cost limitations, only 50 damage scenarios have been selected. The grounding damage index is defined to represent the damage severity for each of the selected scenarios. The residual strength of the ships in the grounding damage scenarios is then calculated using the ALPS/HULL (2012) progressive hull collapse analysis program using intelligent supersize finite element method (ISFEM). Finally, the R–D diagram is established based on these computations.