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4 - Primary Loading of Ship Structures

Published online by Cambridge University Press:  20 March 2025

P. A. Caridis
P. A. Caridis
Affiliation:
National Technical University of Athens
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Summary

In this chapter both hull girder longitudinal bending and torsional loading are treated. Ship-type bodies are considered in both still water and waves (quasi-static loading). The equations for longitudinal bending moment and shear force are obtained. Wave profiles are considered and the use of sectional area curves is illustrated. The balancing procedure of the hull girder on a wave is then described. The various factors that affect longitudinal bending moment and shear force distributions are discussed and reference is made to the Smith effect. Torsional loads are considered next and their generation is described in the case of both closed-deck and open-deck hull forms. Expressions obtained for torsional moments in the past as well as those included in the IACS Common Structural Rules are given. Wave loading of ship hulls is considered and classical linear strip theory is described. The IACS approach to estimating primary longitudinal bending loads and corresponding strength requirements is described. The role of classification societies in ensuring safety and durability is discussed, following which the formulas developed for bending moments and shear forces are presented.

Keywords

longitudinal bending momentlongitudinal shear forcetorsional loadwave loadingstrip theoryIACS loads
Type
Chapter
Information
Global Strength of Ships
Analysis and Design using Mathematical Methods
 , pp. 122 - 171
Publisher: Cambridge University Press
Print publication year: 2025

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