Numerical Analysis Of Nonlinear Dynamic Response And Buckling Based On Defective Stiffened Plates

Stiffened plates are widely used in aerospace, shipbuilding, machinery and other fields as the main load-carrying structure due to the benefit of its light structure and strong bearing capacity. Therefore, it has great value of studying the dynamic response and buckling of the stiffened plates under impact loading. However, it is difficult to use analytical methods to do the research, as the mechanical behavior of the plates and stiffener are coupled and the dynamic response and buckling of stiffened plates under impact loading shows a highly nonlinear structure. Nevertheless, using the finite element method to simulate its numerical value can be treated as a better way. By using large finite element software ANSYS/LS-DYNA, this paper makes a group of numerical simulation of the dynamic response and buckling of stiffened plates under impact loading, which encompasses two aspects:Firstly, this paper establishes groups of finite element models by making the stiffened plates under the transverse impact load as the research object. Through the comparison of the displacement history curves and the stress contour images of stiffened plates with different parameters, the influence of various parameters on the dynamic response is discussed. These parameters include the form of load, the peak of load, the volume ratio of the stiffeners, the aspect ratio of the stiffeners and the form of stiffeners' distribution.Secondly, based on the four edges simply supported stiffened plate models with initial geometric defections, the paper makes the numerical simulation of their dynamic response and buckling behavior under the in-plane impact loads. Through extracting the dynamic response displacement history curves of stiffened plates with different parameters such as initial defection amplitude, the impact duration, the volume and aspect ratio of the stiffeners and the form of the stiffeners'distribution, the P-Y curves based on the B-R criteria are drawn. A preliminary determination of the dynamic buckling of the stiffened plates is made based on the B-R criteria, and the influence of various parameters on the anti-buckling capacity of the structure is discussed. The results show that the dynamic response of stiffened plate and buckling behavior with different load parameters presents significant differences; the dynamic buckling of the stiffened plates is very sensitive to initial defections; the influence of the parameters of stiffening ribs on the dynamic response of stiffened plates has some rules to follow, which are of great practical value to the design of stiffened plate.