Study On Advanced Buckling Analysis Of Stiffened Panels Under Complex Stress

The basic strength member of hull structure is stiffened panels.Therefore,precise assessment of ultimate strength of stiffened panels is very important for ensuring the safety of ship structures.First,the research status of advanced buckling analysis of stiffened panels is introduced.Then,calculation method(EPM)of ultimate strength of plates and stiffened panels is given based on elastoplastic theory.Finally,EPM method of ultimate strength plates and stiffened panels are verified by nonlinear finite element method and model test.The main research work is as follows:(1)EPM method of ultimate strength of unstiffened plates considering shear effect based on elastoplastic theory is presented.Compound and separate analysis method of shear stress and other stress effect are compared and feasibility and high efficiency of the separate analysis method are verified;Comparative study of EPM method with empirical formula and ABS rules is conducted and the influence of various parameters on the ultimate strength of rectangular plates is studied.(2)Failure modes of stiffened panels under complex stress state is combed and the buckling collapse of plate is added as a failure mode of longitudinal stiffened panels with the main load is transverse stress.Calculation formula of tripping of the longitudinal stiffener is revised.EPM method of ultimate strength of stiffened panels based on elastoplastic theory is given.(3)Model and loading device of ultimate strength test of double bottom panels are introduced and initial deflection of test section is given.Comparative study of ultimate strength of the test model using EPM method,nonlinear method and elastic buckling method is conducted.(4)A software system is developed based on EPM method.Comparative study of ultimate strength of four typical stiffened panels under complex stress using EPM method and nonlinear finite element method is conducted..