On the Character of Container Ships

Abstract

This paper describes the summary of the study on the character of container ships from the viewpoint of economy and structural strength based on the actual data of container ships that were taken through the course of the progress of ships. (These data were produced mainly by Mitsubishi Kobe Shipyard with which the author was engaged till recently.) The development of container ships can be observed on two causes; "External factor" and "Internal factor". "High speed" and "Large size". These can be regarded as the natural characteristics of container ships, which conventional cargo liners could not satisfy. Such demand of economics should be called "External factor of development". Another cause called "Internal factor" means "container loading on deck" and "wide and long hatches". These were attained by container ships. It was verified that expected effects on carrying capacity were proven by these characters, by application of various engineering parameters and calculation of economy of ships operation. Existence of these characters was also proven by principal component analysis. Furthermore, container ships have the character on structural design that their principal dimensions are determined in accordance with number of containers stored in holds. The way to future progress of container ships should be considered to utilize further these characters. And, development of total hull girder system in the field of structural design and so called flexible bossings for good performance in the field of resistance and propulsion should be expected. For guidance the word "container ships" appears in this paper is understood to be "lift on lift off type".