Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners

Shuichi Yamatoki, Yoshitaka Hamamoto, Koji Gotoh

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Abstract

In ship hull design, longitudinal stiffeners may be twisted or knuckled to keep the continuity of strength along the vessel. This occurs at angled discontinuities such as discontinuous connections at the transverse web between two longitudinal stiffeners having different angles, e.g., a side shell longitudinal stiffener in the rounded part of the ship's hull. Although the criteria for selection of "twist", "knuckle", or "angled discontinuity" as it is should be strength criteria, there are no generalized criteria or published systematic studies, and ship hull designers usually depend on experimental rules. In this study we evaluate and compare the stress magnification factors and define the relative ratio between the stresses in the discontinuity and continuity structures by using finite element analysis from a strength-of-materials point of view. Our results show that under lateral load conditions the stress factor is larger in the twist structure than in the angled discontinuity structure, although under axial load conditions the stress factor in the knuckle and angle discontinuity structures is larger than in the twist structure. Additionally, we propose a formula that estimates the factor in the knuckle structure based on the strength-of-materials approach.

Original languageEnglish
Title of host publicationStructures, Safety and Reliability
PublisherAmerican Society of Mechanical Engineers (ASME)
ISBN (Electronic)9780791845431
DOIs
Publication statusPublished - Jan 1 2014
EventASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014 - San Francisco, United States
Duration: Jun 8 2014Jun 13 2014

Publication series

NameProceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE
Volume4B

Other

OtherASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014
CountryUnited States
CitySan Francisco
Period6/8/146/13/14

Fingerprint

Ships
Strength of materials
Axial loads
Finite element method

All Science Journal Classification (ASJC) codes

  • Ocean Engineering
  • Energy Engineering and Power Technology
  • Mechanical Engineering

Cite this

Yamatoki, S., Hamamoto, Y., & Gotoh, K. (2014). Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners. In Structures, Safety and Reliability (Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE; Vol. 4B). American Society of Mechanical Engineers (ASME). https://doi.org/10.1115/OMAE2014-24611

Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners. / Yamatoki, Shuichi; Hamamoto, Yoshitaka; Gotoh, Koji.

Structures, Safety and Reliability. American Society of Mechanical Engineers (ASME), 2014. (Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE; Vol. 4B).

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Yamatoki, S, Hamamoto, Y & Gotoh, K 2014, Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners. in Structures, Safety and Reliability. Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE, vol. 4B, American Society of Mechanical Engineers (ASME), ASME 2014 33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014, San Francisco, United States, 6/8/14. https://doi.org/10.1115/OMAE2014-24611
Yamatoki S, Hamamoto Y, Gotoh K. Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners. In Structures, Safety and Reliability. American Society of Mechanical Engineers (ASME). 2014. (Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE). https://doi.org/10.1115/OMAE2014-24611
Yamatoki, Shuichi ; Hamamoto, Yoshitaka ; Gotoh, Koji. / Evaluation of the stress magnification factor in angled discontinuities of longitudinal stiffeners. Structures, Safety and Reliability. American Society of Mechanical Engineers (ASME), 2014. (Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE).
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