Aspects of Rational Structural Design of SWATH Ships

Tolikas, Constantinos (1995) Aspects of Rational Structural Design of SWATH Ships. PhD thesis, University of Glasgow.

Abstract

The aim of the work described herein is to provide the background, underlying assumptions and considerations, as well as describe the tools necessary for the development of reliability-based strength criteria for the design of the structural components of fast, multi-hulled ships (Chapters 1-4) in general, and SWATH ships in particular. An overall view of the current state and future prospects of the fast marine transportation market, highlighting the limitations and advantages of the application of such advanced marine concepts is provided in Chapter 1. The challenges, both strategic and technological, that would have to be overcome before these concepts enjoy a more widespread acceptance from the passengers, operators, and governments, are identified and form the background within which the work described herein develops. It has been inevitable that a large number of topics had to be covered in order to provide the reader with the overall picture of the structural design problems expected and their solutions in this novel form of transportation. As a result, no claim for completeness is made herein, but instead an 'in width' study of the topic was felt as most appropriate for establishing the degree of interrelation and interaction of the various aspects of structural design, and has therefore been actively pursued. The problem of estimation of both primary and secondary loads on SWATH ships is tackled in Chapter 2, by reviewing the options and methods available to the designer. Of the secondary loads, the question of slamming load prediction on the underdeck of SWATH ships has been given some attention, via two sets of drop tests (one by the author) carried out at the Department of Naval Architecture and Ocean Engineering, University of Glasgow and the main results described herein. Current approaches for the determination of fatigue damage loading are also described. Chapter 3 concentrates on the strength modelling aspects and the associated uncertainty as applicable to the fatigue design of both monohull and multi-hull vessels. A brief description of the sources of fatigue strength reduction in welded structures and the possible repair measures, the background to the major steel and aluminium fatigue design codes is presented, coupled with a comparison of the major aluminium fatigue design codes. The probabilistic derivation of partial safety factors for fatigue strength expressions is also presented but not demonstrated. In Chapter 4, the work has concentrated mainly in the area of strength modelling for the various structural components of the SWATH ship under all possible load combinations they might be expected to withstand. Although it stops just short of deriving appropriate partial safety factors for the various structural components and failure modes in a multi-hull structure, detailed guidance on how to do so is provided. The reliability-based design procedure to the structural optimisation, with respect to cost, weight and safety, of an example SWATH ship, the M.V. Patria is applied and described instead in Chapter 5. The conclusions of the research, recommendations on the most appropriate strength formulations and the areas which may benefit from further research are all finally identified in Chapter 6. Note: Description of the various parameters used in individual Chapters is adequately covered in the Notation Section, unless otherwise presented in the text.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Additional Information: Adviser: Douglas Faulkner
• Keywords: Naval engineering
• Date of Award: 1995
• Depositing User: Enlighten Team
• Unique ID: glathesis:1995-75511
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 19:36
• Last Modified: 19 Nov 2019 19:36
• URI: https://theses.gla.ac.uk/id/eprint/75511