Characteristic lengths of modular floating structures (MFSs) : analytical models and potential applications

Abstract

Floating cities, built on floating structures, are seen as an attractive solution to accommodate the increasing costal population and the threat of rising sea levels. Modular floating structures (MFSs) stand out among various types of floating structures, particularly due to the small size of floaters, ease of modular construction, and re-deployment flexibility. The global response of floating structures depends on the ratio of structure length to characteristic length as well as the ratio of structure length to wave length. The characteristic length refers to the area influenced by a local perturbation, such as a concentrated load. While the structure length and wave length are relatively easy to define, determining the characteristic length requires certain efforts. Previous studies on the characteristic length were limited to mat-like (continuous) floating structures, whose models are not applicable to (discrete) MFSs, because the stiffness of MFSs varies significantly at connectors between floating modules. This study fills the knowledge gap by proposing three analytical models, which are validated through numerical simulations based on hydroelastic analysis. Additionally, several potential engineering applications of the proposed models are exemplified. The current study enables the analytical computation of MFSs under various combinations of static vertical loads and moments.