The aim of this paper is to proposes new methods for modelling a very large floating structure (VLFS) with complex connections in the framework of the discrete-module-beam (DMB) hydroelasticity theory, and makes a comparison with the existing methods.

First, a brief introduction of the DMB-based hydroelasticity analysis method is given, followed by procedures for calculating the dynamic response of VLFS under regular waves. A structural stiffness matrix is then defined to model connections with complex forms in VLFS. Corrections are made to the relationship between the forces of two lumped masses and their displacements, obtaining a revised structural stiffness matrix and excitation force matrix, and solving the new hydroelastic equations. Finally, the varying trends of the structural dynamic response of VLFS against different bending stiffness by four methods are explored, and the corresponding reasons for their response differences are analyzed.

The results show that all four methods are capable of precisely predicting the hydroelastic response of VLFS with complex forms of interconnection.

The methods in this paper extend the application of the DMB-based method in predicting the dynamic response of non-continuous VLFS, such as multi-hinged VLFS or VLFS with fracture places.