Dynamic characteristic of damaged ship structures considering the warping deformations

Abstract

For some largely damaged ships, the conventional methods are unadaptable to estimate their dynamic characteristics as to ships with symmetrical hull section. Based on dry hull modal analysis of flexure — torsion coupling vibration of unsymmetrical ship structures about longitudinal center line, a transfer matrix method to calculate the dynamic characteristics is presented. Taken both shear effect and warping deformations into account, the point and field transfer matrices are derived, and the influence on dynamic characteristics is computed according to different damaged positions and ranges. As examples, the damaged structures are calculated and some interesting conclusions are obtained.

Keywords

damaged ship / coupling vibration / warping / dynamic characteristics

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