In the early morning of January 2, 1997, a Russian tanker, the MVNakhodka, broke in two in the Sea of Japan. The fore part of the vessel drifted and was stranded on the coast of Japan, and the aft
part sank. The coast of Japan was seriously polluted by spilled heavy oil. Following this disaster, the Japanese Government
established a Committee for the Investigation of the Causes of the Casualty of theNakhodka. This paper deals with the structural strength of MVNakhodka at the time of the accident. First the structural characteristics of theNakhodka are described, and the reduction in thickness of the structural members are estimated based on the data measured on the fore
part of the vessel which drifted ashose. Then the ultimate longitudinal strength of the hull girder at the time of the accident
is evaluated by applying Smith's method, and the possibility of break-up collapse due to excess loads is discussed. The mechanism
of fracture at the bottom plate is also discussed based on the observed fracture surfuce of the cross section. Finally an
FEM (finite element method) simulation of the break-up of the hull girder is performed. It is shown that buckling/plastic
collapse took place at the deck plate near Fr.153, which was followed by the successive buckling collapse of the side shell
plate of the hull girder. Right after the collapse of the deck structure, the bottom plate fractured just in front of the
transverse bulkhead at Fr.153.
This article is based on an article that appeared in Japanese in the Journal of the Society of Naval Architects of Japan,
vol. 183 (1998). 相似文献
This paper presents an efficient finite element procedure for the collapse analysis of ship hulls under complicated loads. A set of finite elements, such as beam-column elements, stiffened plate elements, and shear panel elements are developed, directly accounting for the geometrical and material non-linearities and initial imperfections.
Elastic-plastic stiffness matrices for elements have been derived by combining elastic large displacement analysis theories with a plastic hinge model. The buckling and post-buckling behaviour of plates is included using an effective width concept. The procedure is effective, since few mode-points are necessary and numerical integration for evaluating stiffness matrices is avoided. Fracture mechanics criteria are introduced in order to account for tension tearing rupture and brittle failure of the material.
Practical applications to ultimate longitudinal strength analysis of ship hulls and tanker collision analysis are presented. The procedure can also be used for collapse analysis of offshore and onshore structures. 相似文献