Finite element study of residual ultimate strength of a double hull oil tanker with simplified collision damage and subjected to bi-axial bending

Abstract

ABSTRACTThe aim of the study is assessment of the residual strength of the double hull oil tanker damaged in collision, which the accidental limit states foreseen by International Association of Classification Societies in their new Common Structural Rules. Collision damage is idealised as a ‘rectangular box’, assuming to start from the main deck downwards. Nonlinear finite element method with the explicit dynamic integration method implemented in LS-Dyna is employed. Such approach enables a systematic investigation of ship residual strength under combined horizontal and vertical bending moments that has not been performed previously. As a result of the study, residual strength interaction diagrams are developed with the purpose of rapid residual ultimate longitudinal strength assessment of the damaged oil tanker. Interaction diagrams may be useful for classification societies when developing rules regarding accidental limit states, as well as for a fast assessment of the hull girder residual strength in accidental situations.