Optimization of Ship-Compartments Arrangement on the Basis of the New Damage Stability Criteria

The paper addresses the problem of damage stability criteria with reference to survival time, that is, the time available for evacuation of passengers on a damaged passenger roll-on/roll-off (RO/RO) vessel undergoing large-scale flooding on the car deck. The current various proposals at the International Maritime Organization (IMO) for the s factor (probability of surviving a given flooding) make no reference to survival time. The paper shows a direct link of the "prime" s factor with the time to capsize. This link has unprecedented value for a flooding control decision support system used during a crisis on board passenger ships but is of no value for the designer for whom the s factor means simply probability of surviving with adequate survival time. The paper shows how to utilize experimental data from 30-minute test runs for survival criteria based on longer duration of tests.

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Damage Stability Requirements for Tankships, Chemical Ships, and Gas Ships

Marine Technology and SNAME News ◽

10.5957/mt1.1976.13.2.121 ◽

1976 ◽

Vol 13 (02) ◽

pp. 121-151

Author(s):

J. W. Kime ◽

R. E. Johnson ◽

W. D. Rabe

Keyword(s):

Stability Criteria ◽

Damage Stability ◽

History Of ◽

Similarities And Differences ◽

International Conventions ◽

Chemical Code

This paper reviews the various U. S. regulations, international conventions and IMCO codes which contain damage stability requirements for tankships, chemical ships, and gas ships. A brief history of damage stability standards and background on the development of the 1973 Pollution Convention, the IMCO Chemical Code, and the IMCO Gas Code are presented. The similarities and differences among the various damage stability criteria and requirements, with emphasis on the determining philosophies and assumptions, are shown. Finally, the type of information to be presented in stability booklets and the extent of calculations required to develop that information are discussed and illustrative examples given. Discussers Angelo P. Ritola Harry D. Johnson R. W. Baseler and T. G. Ogrodnik Merville Willis Tom F. Robinson Larry L. Goldberg W. Michael Walsh William Garzke James B. Robertson Eric Linsner

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Assessment of Survivability of Surface Combatants after Damage in the Sea Environment

Journal of Ship Production and Design ◽

10.5957/jspd.2017.33.2.156 ◽

2017 ◽

Vol 33 (02) ◽

pp. 156-165

Author(s):

Evangelos Boulougouris ◽

Stuart Winnie ◽

Apostolos Papanikolaou

Keyword(s):

North Atlantic ◽

Probabilistic Approach ◽

Weather Conditions ◽

Operating Conditions ◽

Stability Assessment ◽

Stability Criteria ◽

The North ◽

Damage Stability ◽

Damaged Stability ◽

The North Pacific

The operating conditions of modern warships, in the natural sea environment, have a significant influence on their survivability in the event that watertight integrity is lost. Up to now, the consideration of sea and weather conditions has been implicitly accounted for in a naval ship's damaged stability assessment. This article outlines a probabilistic approach to assessing a naval ship's damage stability, in which some of the limitations of the currently used damage stability criteria are identified, including the validity of the assumption of moderate sea states at the time of damage. An investigation of the operability of a frigate design found that there is a significant increase in the risk of a ship's loss when changing the operational area from the North Atlantic to the North Pacific. A remarkable additional finding of the study showed that the assumed distribution for the damage penetration has no significant effect on the ship's survivability because of the way modern combatants are designed.

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A unique application and point of truth for Naval Architecture Calculations

10.5957/wmtc-2015-108 ◽

2015 ◽

Author(s):

Rodrigo Perez ◽

Verónica Alonso

Keyword(s):

Concept Design ◽

Stability Criteria ◽

Power Prediction ◽

Naval Architecture ◽

Complete Control ◽

Intact Stability ◽

Damage Stability ◽

Cad Cam ◽

The Stability ◽

Definition Of

Many tools handle with the calculation of compartment definition, hydrostatics, intact and damage stability and power prediction, but these calculations are separated from the rest of ship CAD/CAM tools. Ship designers need to work closely with the shipyards, in a complex and distributed environment making necessary to have suitable tools at early design stages to ensure profitable projects. Naval architecture is handled in FORAN with a revolutionary approach, where integration and advanced features are the relevant characteristics in a single and complete set of applications that are used in conjunction to other disciplines, from concept design to operation. This new approach groups the former modules for naval architecture available in FORAN from many years, is intuitive and user-friendly. The information is stored in a database instead of a wide set of files. As regards this feature, there are two different alternatives depending on the scope of the project. If the ship designer wants to calculate only naval architecture calculations, the solutions is based on a SQLITE database suitable for a standalone application. This approach benefits a ship design office, in the study of different design alternatives very quickly but having a complete control of them. The other option is integrating the Naval Architecture with the rest of FORAN design disciplines, in a single database based in Oracle. In this case, the great benefit comes from the single truth of data from concept design to operation, which ensures dramatically the reduction of errors and re-work. After the definition of compartments in 3D, by using a very fast application, the module guides the user through the naval architecture calculations with a tree of elements very intuitive, with powerful key algorithms and with a solid representation of spaces. The definition of the necessary entities to make any kind of calculation is very fast. For the intact stability a set of standard stability criteria is provided. It is based in a quick definition of loading conditions, initial situations, flooding conditions and compartment subdivisions. And for the evaluation of the damage stability a set of standard stability criteria are also provided, following deterministic and probabilistic approaches. With these tools any naval architect is able to make very fast all the necessary studies to assure the stability regulations are complied with.

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