Browse by author
Lookup NU author(s): Achinike Ibekwe, Dr Yongchang Pu, Professor Bob Dow
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
With the expectation of hull girder asymmetry and corresponding shift in elastic neutral axis resulting from collision damages and other forms of structural deteriorations, the interaction of vertical and horizontal hull girder capacities become quite significant in the assessment of ship structural safety. This paper therefore extends the application of a previously proposed interactive-numerical probabilistic based methodology for structural safety to assess the hull girder ultimate strength reliability of a damaged ship by means of a user-defined numerical framework. Hull girder capacity is calculated using the NS94D ultimate strength code, which is based on the Smith's progressive collapse method. The resulting deterministic responses have been interactively linked to the NESSUS probabilistic framework so that the reliability of the damaged hull girder is predicted using an implicit limit state function defined based on a transformation of coordinates to appropriately account for any shift in the neutral axis. Random deviations of the constituent variables are directly applied to calculate the ultimate strength deterministic responses, thereby circumventing the need to characterize any correlated strength variable, which is at best subjective. The conventional approach of characterizing ultimate strength by an assumed coefficient of variation and distribution type was found to be conservative in predicting structural safety of ships relative to the proposed method. Application of the interactive-numerical technique for structural reliability is therefore considered significant for problems involving correlated random variables with unknown statistical characteristics. The method is being considered to predict the safety of cracked hull girders by accounting for the residual strength and further load bearing capabilities of deteriorated and adjacent elements.
Author(s): Ibekwe AU, Pu YC, Ham WL, Dow RS
Publication type: Conference Proceedings (inc. Abstract)
Publication status: Published
Conference Name: 33rd International Conference on Ocean, Offshore and Arctic Engineering
Year of Conference: 2014
Print publication date: 01/01/2014
Acceptance date: 08/06/2014
Publisher: ASME
URL: https://doi.org/10.1115/OMAE2014-23210
DOI: 10.1115/OMAE2014-23210
Library holdings: Search Newcastle University Library for this item
ISBN: 9780791845424
