Study On Shear Performance Of Different Welded Structures Of Stiffened Aircraft Panel

The design and analysis of the stiffened panel structure of the aircraft fuselage is a very important part in the manufacture of large aircraft.Dual beam laser welded stiffened panels have the advantages of significantly reducing component weight,good air tightness and greatly reducing the assembly workload,so it has been widely used in the aviation field.The research content of this paper mainly discusses the buckling and post-buckling mechanical properties of stiffened panels under shear loading.Firstly,the shear test of stiffened panel with double laser welding was carried out.The buckling mode,post-buckling bearing capacity and failure mode of stiffened panel under shear loading were analyzed.The buckling and post-buckling modes of the panel were analyzed based on the finite element simulation.The results show that the load-displacement curves obtained from simulation and test are in good agreement,the error for the buckling load by the eigenvalue buckling analysis compared with the test buckling loads is close.The stiffener takes an important part in the post-buckling process,and the slight deformation of the frame results in the unstable loading of the stiffened panel,the connecters will affect the overall stiffness of the stiffened panel.Secondly,shear stability test was carried out by the dual beam laser welding stiffened panel with cover.The buckling load,buckling form,post-buckling carrying capacity and failure modes of the stiffened panel with cover under shear loading were analyzed.A finite element method was utilized to model the stiffened panel and shear fixture.Meanwhile,the effects of cover on the carrying capacity,stress distribution and deformation of cutout stiffened panels were investigated.The simulation results were compared with the experimental results.The opening causes the stress of such stiffened plates to be more complicated,and the shearing load cannot be calculated by the empirical formula of the engineering.The load-displacement curves obtained from simulation and test are in good agreement,and the errors for the buckling loads and failure loads obtained from the numerical calculations compared with the test are close,respectively.The rigidity and load-carrying capacity of open stiffened panel reduce,the cover has a great influence on the stress and out-of-plane deformation.