Research On The Strength Evaluation Method Of Container Ship Based On The Theory Of Hull Girder Load Adjustment

As one of main ship types,container vessels play an important part in international cargo transportation.With the appearance of urtra large container vessels,however,the applicability of traditional rules faces big challenge.There is increasingly requirement for more scientific and reseanable strength assessment on container vessels because of some recent major accidents for container vessels.As the production of IACS to comply with GBS requirement,Harmonized Commen Structual Rules(HCSR)has got extensive attention since it was implemented.Especially in the consideration of hull girder loads,the method has got wide range of approval in the industry by the scientificity and rationality.And the typical high stress areas in container vessels are near the hatch corners in the upper deck levels,mainly bearing the hull girder loads.Such areas are the key areas in the global FE analysis of container vessels.Hull girder loads are taken as the research derection in this paper.Deep research is carried out about the moments caused by longitudinal forces,which are not considered in HCSR,and reviesed formulas are proposed in this paper.Ideal model and actural hold model are used to verify the correction of revised formulas and analyze the influence of moments caused by longitudinal forces,and it could be used toBased on the deep analysis about the method for calculating and adjusting hull girder loads in HCSR,hull girder loads adjusting method aiming at whole ship of container vessels is proposed in this paper.A 10000 TEU container vessel FE model is used to test and verify the method proposed in this paper.Results show that the hull girder loads adjusting method could adjust all hull girder loads to target values in every web frame section and the FEM calculating results agree with the results calculated by some Class Rules for container vessels.Hull girder strength assessment method for container vessels is established in this paper based on the theries of hull girder loads adjustment and equal design wave.And an 18000 TEU container vessel is carried out strength evaluation by the method.Results show that the method could reflect the structural response in the wave pressure and dynamic loads caused by ship body and cargos.And the method could be used to carry out hull girder strength assessment for container vessels.