Numerical and experimental study on motion responses of hinged multiple floating bodies with damaged bottom openings

To address the limited consideration of water flooding in damaged hinged floating bodies within existing research, a numerical model was established to calculate the motion responses of hinged multiple floating bodies with damaged bottom openings. The model employs the Kane method to describe the dynamic behavior of the hinged multibody system and utilizes the modified Bernoulli equation to simulate the water flooding process. Validation of the numerical model was confirmed through model tests conducted in a water flume. Damaged single pontoon and hinged triple-pontoons were selected to investigate the effects of constraint forms, opening sizes, and damage positions on the motion responses of the system. Results indicate that the hinged constraints primarily affect the maximum sinking displacement, whereas the opening size governs the sinking rate, with both factors significantly influencing the time required to reach a stable equilibrium of the system. Furthermore, the system exhibits the greatest vulnerability when damage occurs on the side pontoon, as the transverse shift of the center of gravity triggers significant tilting. Defining the flooding state by coupling the water flooding volume with the overall floating state of the system provides a scientific basis for optimizing compartmentalization design and equipment layout. • A numerical model based on the Kane method and modified Bernoulli equation was validated via water flume experiments. • Constraint form affects maximum sinking displacement, while opening size influences sinking rate. Both impact equilibrium time. • It is dangerous when side damage occurs. Identifying flooding states can guide compartment design and equipment layout.