Investigation of the Nonlinear Rolling of a Ro-Ro Ship with Slipping of Heavy Loads

Abstract

The common effect of waves and the slippage of internal heavy loads will cause a ro-ro ship to roll seriously. This is one of the important reasons when ro-ro ships capsize. The multibody system with a floating base is composed of a ro-ro ship and slipping heavy load. This paper takes the rolling angle of the ship and the transverse displacements of the heavy loads on deck as degrees of freedom. The equations of motion of the system are derived, including the influence of the nonlinear restoring and damping moments due to the influence of the waves. Taking a certain channel ferry as an example, a set of numerical calculations have been carried out for the synchronous effect of slipping heavy loads on a rolling ro-ro ship, the nonlinear rolling response of the ship and the displacement response of the slipping heavy load under the common effect of synchro-slipping heavy loads and wave. The conclusions are that the motion of the numerous freely slipping vehicles synchronize in most cases and the nonlinear rolling angle of the ro-ro ship will increase when considering the nonlinear characteristics.