The Effect of Inner Steel Hull Flexibility on the Responses of the LNG Containment System No.96 under Static Loads

摘要

Stress analyses of LNG containment system (LCS) No.96 have beenrnconducted with the main objective of studying the effect of inner steelrnhull flexibility on the response of LCS No.96. Therefore, two global FErnmodels of LCS No.96 were created with rigid and flexible inner steelrnhull support using combined shell and solid elements. In this study,rnelastic material properties are used. The studied responses are the staticrnstress distributions of LCS No.96, eigen buckling modes and values, asrnwell as their nonlinear geometrical behaviour of the LCS structure withrnimperfections introduced.rnIt was found that the static stress distribution in the upper part of thernprimary box is not affected by the flexibility in the inner steel hullrnwhich supports the LCS No.96. The responses of the lower part of thernprimary box down to the mastic ropes are influenced by the response ofrninner steel hull. The first buckling modes of model are bending modesrnof its secondary bulkheads. The model of LCS NO.96 that accounts forrnthe flexibility of inner steel hull create lower eigenbuckling values thanrnone with rigid support. Imperfections are introduced to the buckledrnbulkhead based on the eigenmodes with maximum initial displacementsrnof 1%, 10% and 50% of the bulkhead thickness. The stress distributionsrnbefore and after the LCS No.96 loss of stiffness are studied.