1.
A specific value for the initial level of obstruction over the keel, δo, is assumed for a known seabed topology, and the draught at the grounding point is first calculated as Drock = DFP − δo where DFP is the draught at the forward perpendicular (FP).
2.
The inertia, damping, restoring matrices and excitation force Fg (x,δ) are computed.
3.
The position of the ship is incremented in the x – direction to a new position, the new draught at the contact point (Drock) is estimated and a new penetration (δ) is also obtained.
4.
The new force corresponding to the penetration found in step (3) based on the set of F − δ curves (which are obtained with FEA) is calculated. The correct values of the contact force and the penetration for the current time step are now found for the known seabed topology. The buoyancy and pitch moment induced by grounding forces are updated.
5.
The dissipated energy and potential energy for the current time step are updated with Eq. (14). The total energy is checked against the initial kinetic energy at each step of the iteration based on Eq.