Study On Stability Of Composite Open Thin-Walled Stiffened Plates

In this paper,based on carbon fiber bismaleimide resin composite stiffened panels,experimental research and Simulation Analysis on the failure mechanism of composite stiffened panels were carried out.The main contents of this paper include:(1)The basic mechanical properties and fatigue properties of composite laminates were tested.Quasi-static tensile and compressive tests were carried out on Composite Laminates at different temperatures,and their high temperature mechanical properties were analyzed.Based on the static data,the tensile fatigue and compressive fatigue tests of the laminates were carried out under different temperature environments,and the effect of temperature on the fatigue life of the laminates was analyzed.(2)Quasi-static compression test and simulation analysis were carried out for composite open-ended thin-walled stiffened plates.In the experiment,the strain distribution in the test section of stiffened plate was obtained by DIC optical nondestructive testing technology,and the failure mode was analyzed according to the experimental phenomena.Abaqus finite element analysis software is used to simplify the modeling of stiffened plates.The good consistency between the finite element simulation results and the experimental data verifies the rationality of the method.At the same time,the failure modes of composite open thin-walled stiffened plates under compressive loads are revealed.(3)The shear stability of composite thin-walled stiffened panels with openings is studied experimentally and simulated.Firstly,the stiffened plate structure and fixture are optimized to achieve the test effect of pure shear stress field.The strain distribution on both sides of the stiffened plate is obtained by combining the strain gauge and the fiber Bragg grating sensor.The shear post-buckling behavior of the stiffened plate structure is studied by combining the experimental phenomena.The stability and bearing capacity of stiffened plate structure are calculated by finite element method,and the results are compared with the test results,which can provide experimental and analytical reference for the engineering application of this type of structure.