A Modified Nonlinear Hydrostatic Analysis Method for Calculating the Equilibrium Attitude of a Stranded Ship

Stranding accidents of fishing boats and commercial ships are a frequent occurrence. To minimize the loss of life and property in these accidents, a refloating plan for salvage operations is necessary. The best refloating plan is a plan for moving, adding, and removing cargo inside the stranded ship in such a way that the ground reaction force acting on the ship is minimized. To achieve this, it is necessary to quickly calculate the stranded ship to an equilibrium attitude. In this study, we derived a modified nonlinear hydrostatic analysis method for finding the static equilibrium attitude of a stranded ship by combining the effect of ground reaction force. We introduced coordinate transformation matrix between ship coordinate and reaction force coordinate to modify the equation. The procedure of finding the equilibrium position of a stranded ship is also proposed. Finally, when the barge and VLCC were stranded, the equilibrium attitude could be successfully calculated by changing the stranding point.