Nonlinear Numerical Calculation Of Buckling Modes Of Stiffened Plates

With the development of the trend of the ship's light and large scale,the ultimate strength of the hull structure has been widely paid attention to.The stiffened plate is the main bearing member on the body of the hull structure,so the ultimate strength of the ship structure is mainly determined by the stiffened plate.At present,the research at home and abroad is mainly based on the static load of one time loading,and the ship will be subjected to cyclic loads such as attack and collision during the course of navigation.Therefore,the cyclic loading of stiffened plates can accurately simulate the loads of ships during actual voyage.In this paper,a nonlinear finite element method is used to calculate the different buckling modes of the stiffened plate of a ship,as well as the influence of the size of reinforcement,the cycle load,the number of cycles and the loading mode of cyclic loading on the flexion mode.The main contents are as follows:In order to determine the accuracy and reliability of the finite element method,the nonlinear finite element calculation results are compared with the experimental values,the theoretical values and the foreign software calculation results.The finite element method is used to calculate the ultimate strength of the hull plate structure under one time loading and cyclic loading.The two calculation results are compared to analyze the change of the ultimate strength of the stiffened plate under cyclic loading.According to the stiffened plate structure,the nonlinear finite element method is used to calculate the unidirectional and two-way cyclic loading,and the buckling mode and the ultimate strength of the stiffened plate structure under cyclic loading are analyzed.In this paper,20 different cyclic loading methods are set up,and the nonlinear finite element method is used to calculate the ultimate strength of stiffened plate structure under cyclic loading,and the influence of tension,compression cycle load,cyclic loading amplitude and side pressure on the ultimate strength of stiffened plate is analyzed.Six typical buckling failure modes of stiffened panels are discussed.The buckling principle,characteristics and failure of stiffened panels are analyzed.Sixteen kinds of cyclic loading methods are selected to calculate the buckling mode of stiffened plates under different cyclic loading modes.The most common type of buckling mode and which type of buckling mode is more destructive to the stiffened plate structure.Threestiffeners with different stiffeners were selected to analyze the influence of stiffeners on the buckling modes of stiffened panels.The effects of stiffeners on the buckling modes of stiffened panels were analyzed.The six buckling modes of stiffened plates are compared,and the buckling modes of stiffeners before plate failure are analyzed.Different cyclic loading methods are adopted to analyze the bearing capacity of different stiffeners,and the influence of reinforcement size on ultimate bearing capacity of stiffeners is discussed.The nonlinear buckling of stiffeners is calculated before the plate failure buckling mode,and the effect of different loading and stiffened plate size on the failure of the stiffeners is discussed.Based on the ANSYS_PDS module,the influence of different stiffener parameters on buckling modes of stiffened panels is analyzed by using random sensitivity analysis.Based on actual ship stiffened plate,the influence of stiffener parameters on buckling modes of stiffened plates is analyzed,and suggestions for structural improvement are given.