Researches On Buckling And Vibration Characteristics Of Membrane Structures

With the advantages of light, flexible, and functional, membrane structure can be made into space inflatable structures, which can fold efficiently and deploy in a reliable way. The light weight and small packing volume of space inflatable structure reduce the cost of researching and manufacturing. Membrane structure has obvious characteristics of large deformation under external load for its small bending stiffness, and it’s prone to buckling and become wrinkled. The existence of wrinkle will affect the surface shape accuracy and stability of membrane, thus affect the dynamics characteristics of membrane structures. Therefore, the researches on the buckling and its influence on vibration characteristics of membrane structure are of great significance.This paper studies the buckling and vibration characteristics of membrane structure. The research methods on buckling and vibration characteristics of membrane structure were mastered by numerical calculation, experimental test and theoretical analysis. The critical buckling load and wrinkle configurations of membrane structure under different conditions were obtained, and the influence of wrinkle on the vibration characteristics of membrane structure was discovered.The buckling and vibration characteristics of membrane structure under torsional load in center were studied by numerical calculation. The critical buckling load and corresponding buckling mode were obtained through buckling analysis. Membrane structure containing defects was obtained by direct perturbation method, and then, the wrinkle configurations under different torsional loads in center were obtained by nonlinear finite element buckling analysis. In addition, the influence of structural parameters(diameter ratio, elastic modulus, thickness) on critical buckling load was studied. The influence of buckling on vibration characteristics of membrane structure was analyzed through the modal analysis on both membrane structure of pre-buckling state and post-buckling state.The non-contact measuring method based on digital image correlation technique was used to test the buckling and vibration characteristics of membrane structure. The wrinkle configurations and vibration modal of membrane structure under torsional load in center were tested. The error between experimental test and numerical calculation was explained.The buckling analysis of polar orthotropy membrane with different reinforced direction was carried out by numerical calculation. Comparing the critical buckling load and buckling mode of polar orthotropy membrane structure with those of isotropic membrane structure, a certain rule was found. The similarities and differences on configurations between polar orthotropy membrane structure and isotropic membrane structure under same loading were obtained through nonlinear finite element buckling analysis. In addition, the modal analysis on both polar orthotropy membrane structure of pre-buckling state and post-buckling state was carried out. The influence of buckling on vibration characteristics of polar orthotropy membrane structure was same as isotropic membrane structure.The buckling of membrane structure under torsional load was studied through theoretical analysis. The buckling of polar orthotropy membrane structure under torsional load in center was analyzed, and the non-dimensional bifurcation equation was given. For isotropic membrane structure, for example, the critical buckling load and wrinkle configurations were solved by using finite difference method. Comparing the wrinkle configurations simulated by MATLAB with the results of experimental test, the results are basically identical.