Research For Direct Calculation Of Bulk Carrier’s Structural Strength Based On CSR

The key technical points of The Common Structure Rules for Bulk Carrier (CSRBC) include net scale concept, design loads, hull girder ultimate strength analysis, direct calculation of yield, buckling strength and fatigue, etc. There are a lot of bright spots, including using a new model of corrosion, using the advanced wave load model to make the external load more reasonable, using the direct calculation technology which is more suitable for large ship design. HCSR not only inherited the advantages of CSR, but also harmonize loads, hull girder strength and its prescriptive requirements, finite element analysis, fatigue strength, and buckling strength of carrier bulk, making specification content more comprehensive, more emphasis on the role of computational analysis.The main purpose of this paper is to study the direct strength analysis theories and methods in the CSR_BC and HCSR specification. After meeting the yielding strength assessment, the buckling strength is analyzed. Buckling strength assessment is very important in the analysis of the entire structure of the ship. The main contents are as follows:1) The general idea about direct calculation of bulk carrier structure in CSR_BC and HCSR Rules was summarized, including FE modeling of ship structures, dealing with the boundary conditions, choosing the loading condition, calculating the load, solving and analyzing the results.2) The hold FE model of a82000DWT single-hull bulk carrier was established to carried out direct calculation and assessment of the structural yielding and buckling strength according to the CSR_BC and HCSR.3) Though the dividing of elementary plate panel, the buckling strength was analyzed and checken for the main structural members of the ship based on the stress results from the direct calculation of yielding strength.4) By comparing the results of the two specifications, the loading conditions of CSR_BC and HCSR, and the stress of ship members were analyzed to conclud that the direct calculation of HCSR is more reasonable, comprehensive. The following conclusions can be drawn by the yield and buckling strength analysis, in CSR_BC specification, the main structures in the evaluation area meet yield and buckling strength condition request. The structural strength of the corresponding members can not met HCSR specification strength criterion, and most of the major components on the plate panel cannot meet the requirements of buckling strength.