Primary Loading of Ship Structures

P. A. Caridis

doi:10.1017/9781009465892.005

4 - Primary Loading of Ship Structures

Published online by Cambridge University Press: 20 March 2025

P. A. Caridis

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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 moment longitudinal shear force torsional load wave loading strip theory IACS loads

Type: Chapter
Information: Global Strength of Ships
Analysis and Design using Mathematical Methods
, pp. 122 - 171

DOI: https://doi.org/10.1017/9781009465892.005 [Opens in a new window]

Publisher: Cambridge University Press

Print publication year: 2025

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References

Abrahamsen, E. (1958) The Strength of Dry Cargo Ships. Europ. Shbldg. Vol. 7 No. 3 p. 62 & No. 4 p. 35.Google Scholar

Abrahamsen, E. (1967) Recent Developments in the Practical Philosophy of Ship Design. Trans SNAME, Spring Mtg. Montreal.Google Scholar

American Bureau of Shipping (2018) Rules for Building and Classing Steel Vessels. Part 5C - Specific Vessel Types. Chap. 5: Vessels Intended to Carry Containers (130-450 meters in length) 619–950.Google Scholar

Beck, R. F. Cummins, W. E. Dalzell, J. F. Mandel, P. Webster, W. C. (1989) Motions in Waves. In Lewis, E. V. (Ed) Principles of Naval Architecture (Second Revision) Vol. 3 Motions in Waves and Controllability. Jersey City, NJ: SNAME 1–190.Google Scholar

Biles, J. H. (1908) The Design and Construction of Ships. Vol. 1 – Calculations and Strength. London: C. Griffin & Co Ltd.Google Scholar

Clayton, B. R. Bishop, R. E. D. (1982) Mechanics of Marine Vehicles. London: E. & F.N. Spon.Google Scholar

Conn, J. F. C. Miller, N.S. (1961) The Effect of Various Factors on Wave Bending Moments. Transactions NECIES Vol. 77 107–190.Google Scholar

Det Norske Veritas (2005) Hull Structure Course.Google Scholar

Euler, L. (1759) Examen des efforts qu’ ont à soutenir toutes les parties d’ un vaisseau dans le roulis et dans le tangage ou recherches sur la diminution de ces mouvemens (Study of the efforts needed to sustain all parts of a vessel in rolling and pitching, or investigations on the reduction of these motions). Paris: Acad. Roy. Sc. (published 1771).Google Scholar

Evans, J. H. (Ed) (1975) Ship Structural Design Concepts. Centreville, MD: Cornell Maritime Press.Google Scholar

Evans, J. H. (Ed) (1983) Ship Structural Design Concepts – Second Cycle. Centreville, MD: Cornell Maritime Press.Google Scholar

Faltinsen, O. (1993) Sea Loads on Ships and Offshore Structures Cambridge: Cambridge University Press.Google Scholar

“File:Fjordn Surface Wave Boat.Jpg.” n.d. Wikimedia.Org. Accessed January 6, 2021b. https://commons.wikimedia.org/wiki/File:Fjordn_surface_wave_boat.jpg.Google Scholar

Fukuda, J.-I. (1967) Theoretical Determination of Design Wave Bending Moments. Japan Shipb. & Mar. Eng. Vol. 2 No. 3 13–22.Google Scholar

Gerstner, F. J. (1802) Theorie der Wellen (Theory of Waves). Prague: Abhand. Kön. Böhmischen Gesel. Wiss.Google Scholar

Grim, O. (1953) Berechnung der durch Schwingungen eines Schiffskörper erzeugten hydrodynamischen Kräfte (Calculation of the hydrodynamic forces generated by oscillations of a ship’s hull). Jahr. Schiffbau. Gesell. Vol 47 277–299.Google Scholar

Guedes, Soares C. et al. (2000) Loads. Rept. of Technical Committee I.2 in: Ohtsubo, H. Sumi, Y. (Eds) Proc. 14th Int. Ship & Offsh. Struct. Cong. Vol. 1. Amsterdam: Elsevier 63–132.Google Scholar

Guedes, Soares C. Fonseca, N. Pascoal, R. (2004) Long term prediction of non-linear vertical bending moments on a fast monohull. Applied Ocean Research Vol. 26 288–297.CrossRef Google Scholar

Guedes, Soares C. (1992) Discussion on Nitta A. et al.: Basis of IACS Longitudinal Strength Standard Mar. Struct. Vol. 5 559–561.Google Scholar

International Association of Classification Societies (1997) Bulk Carriers. Guidance and Information on Bulk Cargo Loading and Discharging to Reduce the Likelihood of Over-stressing the Hull Structure.Google Scholar

International Association of Classification Societies (2006) Common Structural Rules for Oil Tankers. Background Document. Section 2 – Rule Principles.Google Scholar

International Association of Classification Societies (2020) Common Structural Rules for Bulk Carriers and Double Hull Oil Tankers.Google Scholar

International Association of Classification Societies (2020) Longitudinal Strength Standard. Unified Requirement S11 (Rev. 10) in: Requirements concerning Strength of Ships.Google Scholar

International Association of Classification Societies (2010) Minimum Longitudinal Strength Standards Unified Requirement S7 (Rev. 4) in: Requirements concerning Strength of Ships.Google Scholar

Jacobs, W. R. (1958) The Analytical Calculations of Ship Bending Moments in Regular Waves. J. Ship Res. Vol. 2 20–29.CrossRef Google Scholar

Korvin-Kroukovsky, B. V. (1955) Investigation of Ship Motions in Regular Waves. Trans SNAME Vol. 63 386–418.Google Scholar

Korvin-Kroukovsky, B. V. Jacobs, W. R. (1957) Pitching and Heaving Motions of a Ship in Regular Waves. Trans SNAME Vol. 65 590–615.Google Scholar

Motok, M. D. Jovović, J. (2007) Wave-induced Shear Force and Bending Moment for Service of Ships – Comparison & some Interpolation Procedures. In Developments in Classification and International Regulations. RINA Conf. 24–25 Jan; London; 111–118.Google Scholar

Newman, J. N. (1977) Marine Hydrodynamics. Cambridge, MA: MIT Press.CrossRef Google Scholar

Nitta, A. Arai, H. Magaino, A. (1992) Basis of IACS Unified Longitudinal Strength Standard. Mar. Struct. Vol. 5 1–21.CrossRef Google Scholar

Nitta, A. et al. (1994) On C. Guedes Soares Discussion of Paper by A. Nitta et al. ‘Basis of IACS Longitudinal Strength Standard’. Vol. 5 No. 1, 1992, 1–21. Mar. Struct. Vol. 7 567–572.CrossRef Google Scholar

Ogilvie, T.F. (1964) Recent Progress Towards the Understanding and Prediction of Ship Motions Proc. 5th Symp. Naval Hydr. Washington, DC: ONR.Google Scholar

Papanikolaou, A. (1988) Ship Design Vol. 1: Preliminary Design Methodology (Μελέτη Πλοίου Τόμος Α: Μεθοδολογία Προμελέτης) Athens (in Greek).Google Scholar

Papazoglou, V. Bardis, L. (1989) Ship Statics and Dynamics. (Στατική και Δυναμική Πλοίου ΙΙ) Lecture notes Div. Mar. Struct. Sch. Naval Arch. & Mar. Eng. NTUA Athens.Google Scholar

Paulling, J. R. (1988) Strength of Ships. In Lewis, E. V. (Ed) Principles of Naval Architecture Second Revision Vol. 1 Stability and Strength. Jersey City, NJ: SNAME 205–299.Google Scholar

Pedersen, P. T. (1985) Torsional Response of Containerships. J. Ship Res. Vol. 29 194–205.Google Scholar

Rawson, K. J. (1976) Structural Design Criteria. Lecture Notes RCNC Office Dept. Mech. Eng. Univ. Coll. London Univ. of London.Google Scholar

Rawson, K. J. Tupper, E.C. (2001) Basic Ship Theory Vol. 1 Hydrostatics and Strength. 5th ed. Oxford: Butterworth Heinemann.Google Scholar

Reed, E. J. (1871) “On the unequal distribution of weight and support in ships, and its effects in still-water, in waves, and in exceptional positions on shore”. Phil. Trans. R. Soc. Lond. 161, 413–465.Google Scholar

Robb, A. M. (1952) Theory of Naval Architecture. Glasgow: Charles Griffin & Co Ltd.Google Scholar

Salvesen, N. Tuck, E. O. Faltinsen, O. (1970) Ship Motions and Sea Loads. Trans SNAME Vol. 78 250–287.Google Scholar

Smith, W. E. (1883) Hogging and Sagging Strains in a Seaway as Influenced by Wave Structure. Trans INA. Vol 24 136–153.Google Scholar

Stokes, G. G. (1849) On the Theory of Oscillatory Waves Trans. Camb. Philos. Soc. Vol. 8 441–455.Google Scholar

Temarel, P. et al. (2009) Loads. Committee I.2 Rept. in Jang, C. D. Hong, S. Y. (Eds) Proc. 17th Int. Ship & Offsh. Struct. Cong. Vol. 1. Seoul: Seoul University Press 127–210.Google Scholar

Thomas, G. (2011) Ship Global Response in Still-water. Lecture notes Australian Maritime College.Google Scholar

Ursell, F. (1954) Water Waves Generated by Oscillating Bodies. Quart. J. Mech. & Appl. Math. Vol. 7 427–437.CrossRef Google Scholar

Vedeler, G. (1924) On the Torsion of Ships. Trans. INA 164.Google Scholar

Wah, T. (Ed) (1960) A Guide for the Analysis of Ship Structures. Washington, DC: US Department of Commerce.Google Scholar

Weinblum, G. St. Denis, M. (1950) On the Motion of Ships at Sea. Trans SNAME Vol. 58 184–248.Google Scholar

Wehausen, J. V. (1971) The Motion of Floating Bodies Ann. Rev. Fl. Mech. Vol. 3 267–268.CrossRef Google Scholar