Analysis On Longitudinal Ultimate Strength Of A Large Damaged Vessel

In recent years,the limit state design method based on structural ultimate strength has been developed rapidly in the field of structural engineering.The research on the calculation method of ultimate strength of ship hull has become an important research direction in the research of ship structure strength calculation and design method.The world maritime organization and the main classification societies also present the calculation and assessment of the ultimate strength of ships as a requirement.For the ultimate strength of the ship the classification society puts forward the strength requirements of the original design to ensure that the failure rate is less than 5% within 96 hours of the typical damage mode of the ship under the sea condition of 80%.However,at present,the calculation method of the ultimate strength of the damaged ship is still based on the standard formula.With the rapid development of the finite element theory and the Smith theory,the ultimate residual strength of the damaged ship needs to be further studied.Therefore,this paper focuses on the calculation of the residual strength capacity of damaged hull,and provides the guarantee for the calculation of the ultimate residual strength of damaged ship.In this paper,the residual strength capacity of damaged ship is analyzed.In order to determine the form of ship damage,this paper firstly analyzes the position and typical damage mode of the damaged ship.Comprehensive analysis of ABS,CCS and LR on the break of the damaged ship requirements,puts forward 2 typical break modes,and using the finite element method and simplified calculation method of Smith to analyze.Based on the elastic-plastic finite element method analyze the ultimate strength capacity.Considering the influence of initial ship longitudinal ultimate strength deformation defects and residual stress of defects,and the ultimate stress of the ship under different break are analyzed,the damage characteristics of stress distribution of ship structure under.Considering the two position and break break break model shape and size was calculated based on the simplified Smith,longitudinal residual ultimate bending moment of ship in different damage mode were calculated and plotted bearing envelope longitudinal ultimate under different working conditions of damaged ships,and the remaining limit for different damage forms of bearing to obtain a series of conclusions of comparative analysis.Finally,according to the research results,combined with the work content of the preliminary,a comparative analysis of the characteristics of residual ultimate strength under different conditions of large ship is damaged,and the longitudinal strength of damaged ship calculation provided a series of recommendations to provide support for the follow-up work.