Wang and Ohtsuho gave a set of formulae about the failure mode of the plate, which were used to analyze ship side collision and grounding. Wang and others have done a group of tests concerning the internal mechanics of the deformation mode and energy absorption for double-hull ships during collision or grounding. Hysin and Scharrer have successfully completed a series of calculations of ship roll-on–roll-off with a simplified method, and predicted the collision force, collision depth curve, absorbed energy–collision depth curve, and size of the damage area in the ship's side.
Paik made the finite element analysis program ALPS/SCOL, which was used to calculate the side structure response of the struck ship under the collision of the rigid ship bow. The program chooses the technology of the nonlinear element, which can reduce the amount of time and modeling work.
The SIMCOL program, introduced by Brown, can be used to analyze the internal and external dynamics of the collision in the time domain. The DAMAGE program introduced by Simonsen can be used to analyze the ship structure under collision, and has accounted for deformation of the ship bow since version 5.0. The DTU model program developed by Pedersen and Zhang can be used to analyze the external dynamics of the ship collision.
Figure 23.3 shows the procedure for the potential loss of property (PLP) calculation in ship–ship collision cases (Youssef et al., 2014a). PLP is defined as the product of the collision frequency and the corresponding economic consequence of each individual scenario. It can represent the asset risk associated with accidents. First, a targeted structure is identified in terms of its principal particulars and structural design characteristics. Then, FEMs for both the struck and the striking ship are established. In the models, the element type, mesh size, structural material model, failure mode, and surrounding water effects are identified. Explicit collision simulations are conducted using nonlinear FEM to calculate the structural damage to the targeted ship. The amount of damaged steel is then calculated. The repair costs for the damage replacement can be estimated according to the amount of damaged steel. Once the frequency of ship–ship collision for each scenario is determined, PLP can be calculated by summing the products of the frequencies and their respective repair costs.