Buckling Analysis Of Metal Composite Plates Under Nonlinear Load

In aeronautics,astronautics,bridges,automobiles,machinery and other engineering fields,the effectiveness of structure is a problem that needs to be concerned.So we require structural materials with high strength and light quality.Composite materials can meet the requirements of these areas,so they have been widely used.The metal composite plates have been widely used as a kind of composite materials,and when they are subjected to in-plane compression,shear and bending loads,a common failure mode is the loss of stability,referred to as the "instability" or "buckling".In order to ensure the safety of the structure,the stability analysis is needed.So far,there have been a lot of research on the stability analysis of composite plates under uniform or linear compression load,but few studies have been made on the problem of instability under nonlinear load.However,it is often nonlinear load that in the process of production and use of metal composite plates.Therefore,this paper focuses on the study of the instability of the metal composite plates under nonlinear load.Firstly,considering the simply supported boundary conditions and setting the corresponding deflection function,we deduced the deformation energy of the metal composite plates under the condition of critical buckling,according to the mechanical hypothesis of composite plates in the case of small deformation.The critical load model is set up by introducing the discriminant factor,and the work done by the external force is obtained.According to the principle of conservation of energy,the expression of the discriminant factor is derived,and the model of the instability is obtained.Secondly,based on the theory of large deformation and the minimum energy principle,the post buckling analysis model of metal composite plates was derived by setting the transverse and longitudinal displacement functions.The parameters such as wave height and wave width were obtained by numerical method,and the stress of transverse and longitudinal direction of the metal composite plates were obtained.And the results were analyzed and compared.Finally,a kind of experimental device was designed to study the buckling of the plates,and the formula of the thickness distribution of the cushion blocks corresponding to different distribution load was deduced.The buckling experiments were carried out on the InspektTable100 electronic universal tensile testing machine,and the experimental data,the related literature results and the results calculated by this paper were compared,which verified the correctness of the model.