The Dynamic Buckling And Post-buckling Of The Plates Under In-plane Step Loading And The Influence Of The Dynamic Buckling Under Initial Defect

Plate is one of the widely used in engineering structures. The problem ofbuckling and post-buckling under axial load has been one of the hot researchtopic, and has attracted great attention of many researchers. With the rapiddevelopment of aerospace, atomic energy, automobile, shipbuilding, chemicalindustry etc., dynamic buckling of plates is also gaining more and moreattention, especially the study of the initial defects of plate is the researchfocus. Based on this, the paper made the following work:Firstly,the present researches and background on buckling andpost-buckling are summarized, the buckling of plate and initial defect plate aresimply generalized, and the main methods and conclusions are summarized.Secondly, according to the classical theory of plates and shells, the largedeflection nonlinear dynamic equilibrium equation is derived. Considering theeffect of stress wave, using the method of separation of variables, buckling ofplate are analyzed. The analytic expressions and modal equations of dynamicbuckling critical load of plate under in-plane step loading is gained.Thirdly, the plate dynamic post-buckling equations difference form isderived based on finite difference method. Take the buckling equation as theinitial conditions of post buckling analysis. Using MATLAB to solve the numerical solution of rectangular plates under in-plane step loading and thedifferent boundary conditions of dynamic post-buckling. By changing thesmall amplitude parameters and impact velocity, revealing the initial mode andsmall amplitude value and impact velocity of the rectangular plates dynamicpost-buckling influencing the dynamic post-buckling of plate.Fourthly, a research on the buckling time of initial defect plates withdifferent forms of defects under axial compression in different boundaryconditions was carried out using ABAQUS/Explicit. Based on the bifurcation ofthe history curve of surface symmetry of finite element model, buckling pointthat corresponds to the time for buckling time. The results show that thedifferent defect amplitude and length has great effect on the buckling time.