Graphical presentation of hull frequency data and the influence of deck-houses on frequency prediction¹

Article type: Research Article

Authors: Johnson, A.J. | Ayling, P.W.

Note: [1] Paper read before the North East Coast Institution of Engineers and Shipbuilders, 1st April 1957.

Abstract: The paper is concerned with the presentation of ship-vibration data in a form aimed at enabling quick estimates of frequencies to be made at the design stage. The subject matter represents one aspect of a comprehensive programme of work on ship vibration being carried out by the British Shipbuilding Research Association. Previously published methods have been adapted for this purpose, but in the light of further experimental results obtained by the Authors, it has been possible to extend these methods and suggest certain modifications intended to improve the accuracy of the estimates. Detailed consideration is given to the flexural rigidity of ships having deck-houses. On the basis of a recently published method for estimating the distribution of longitudinal stresses in deck-houses, a series of calculations was carried out for a wide range of ships in order to derive graphs from which inertia correction factors can be readily obtained. Examples are given illustrating the derivation and use of these factors.

DOI: 10.3233/ISP-1958-54404

Journal: International Shipbuilding Progress, vol. 5, no. 44, pp. 178-197, 1958