Response of Thin Walled Metallic Structures to Underwater Explosion: A Review

The thin-walled stiffened cylindrical shells are usually applied in a submarine which takes the external pressure load, or in a boiler, pressure vessel or pipeline system which takes the internal pressure load. The thin-walled stiffened cylindrical shells under hydrodynamic loading are very sensitive to geometrical imperfections. This study is investigating an imperfect thin-walled stiffened cylindrical shell (out-of-round ratio is ψ = 2%) at a depth of 50m below the water level to see how it withstands sideward TNT 782 kg underwater explosion loading so as to understand its structural transient response. ABAQUS finite element software is used as an analysis tool in the current study, meanwhile, during the analysis process, the Fluid-Structure Interaction (FSI) condition is employed. The structural transient response results of stress and displacement time history of the imperfect thin-walled stiffened cylindrical shell can be used as a reference for the anti-underwater explosion analysis and design of future submersible vehicles, pressure hulls or related structural designs.

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The FITNET Fracture Module: Developments and Content

24th International Conference on Offshore Mechanics and Arctic Engineering: Volume 3 ◽

10.1115/omae2005-67563 ◽

2005 ◽

Author(s):

Stephen Webster

Keyword(s):

European Commission ◽

European Countries ◽

Technical Development ◽

Framework Programme ◽

Metallic Structures ◽

British Standard ◽

Thin Walled Structures ◽

The Usa ◽

Thin Walled

FITNET is a four-year European thematic network with the objective of developing and extending the use of fitness-for-service (FFS) procedures for welded and non-welded metallic structures throughout Europe. It is partly funded by the European Commission within the fifth framework programme and commenced in February 2002. The network currently consists of about 50 organisations from 17 European countries but also includes contributions from organisations in the USA, Japan and Korea. Further information can be found in the FITNET TN website: http://www.eurofitnet.org. The FITNET FFS Procedure is built up in four major analysis modules namely; Fracture, Fatigue, Creep and Corrosion and the procedure is being developed for completion in early 2006 in the form of CEN Document. The aim of this paper is to present the features, main analysis routes and major areas of technical development pertinent to the Fracture Module of the FITNET FFS Procedure. The procedure is based on previous developments carried out within the SINTAP project as well as advances in other standards such as the British Energy R6 rev 4 and the current amendments to the British Standard BS7910. In addition the work from other EU projects has been used to extend the treatment of several problem areas, such as the effect of constraint and the treatment of thin walled structures.

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Working Stresses for Columns and Thin-Walled Structures

Journal of Applied Mechanics ◽

10.1115/1.4012225 ◽

1933 ◽

Vol 1 (4) ◽

pp. 173-177

Author(s):

S. Timoshenko

Keyword(s):

Mechanical Properties ◽

Elastic Stability ◽

Structural Elements ◽

Metallic Structures ◽

Thin Walled Structures ◽

Thin Walled

Abstract In metallic structures such as airplanes, airships, ships, bridges, etc. slender bars, thin webs, and thin-walled tubular members are very often used. In choosing working stresses for such structural elements, not only the mechanical properties of the material but also the elastic stability of these elements should be considered. The method of choosing working stresses for such structures is illustrated in this paper by several examples.

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Dynamic Mechanical Behaviour of Innovative Structures Incorporating Cork

Materials Science Forum ◽

10.4028/www.scientific.net/msf.587-588.599 ◽

2008 ◽

Vol 587-588 ◽

pp. 599-603 ◽

Cited By ~ 1

Author(s):

C.P. Gameiro ◽

José Cirne

Keyword(s):

Mechanical Behaviour ◽

High Strain ◽

Strain Rates ◽

The Finite Element Method ◽

Metallic Structures ◽

Dynamic Mechanical ◽

Numerical Tests ◽

Absorbing Material ◽

Thin Walled ◽

Energy Absorbing

Cork is a natural cellular material which has been used for centuries, in natural and agglomerate forms, mainly for applications related to the wine, the automotive and the construction industries. It is a very durable and ecological material, used for thermal, acoustic and vibrating insulation as well as packaging, among others. This paper highlights some of the aspects of a topic of great interest, not much explored yet, which consists of the study of the dynamic mechanical behaviour of innovative structures incorporating cork, dedicated to energy-absorption. Experimental and numerical tests, using the finite element method software LS-DYNA™, were performed in order to evaluate the effects of filling agglomerate cork inside thin-walled metallic tubes, with variable geometries and thicknesses, impacted uniaxially at quasi-static and high strain rates. Some relevant comparisons were carried out and the results obtained allowed concluding that cork might be a viable energy-absorbing material for application in some metallic structures subjected to impact loadings.

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