Study On Dynamic Stability Of Glass Fiber Composite Laminated Plates

Glass fiber reinforced composite(GFRP)laminates are widely used in buildings,bridges,machinery,aerospace,ship,vehicle manufacturing and other fields.Because of the structure of GFRP laminate is lightweight and high strength,its dynamic instability under the action of wind load,earthquake load and other dynamic loads is more prominent.Therefore,the dynamic stability of four-edge simply supported GFRP laminates subjected to longitudinal periodic loading is studied by means of theoretical analysis,numerical simulation and experimental verification.The main research contents are as follows:(1)Derivation and solution of the Mathieu equation for rectangular GFRP laminates with four-edge simply supported.Based on the large deflection theory of von-Karman plate and the third order shear deformation theory,energy-variational method is adopted to derive the dynamic balance differential equation of four-edge simply supported rectangular GFRP laminated plates under the action of longitudinal periodic load,the dynamic balance differential equation is translated into Mathieu equation by using the Galerkin method,the third-order approximate periodic solution about Mathieu equations of GFRP laminated plates is solved by means of characteristic value,the dynamic instability region and nonlinear vibration response of GFRP laminates under parameter instability are obtained.(2)Parameter analysis of dynamic instability of rectangular GFRP laminated plates with four-edge simply supported.The influence of the ply angles,aspect ratio,length-to-thickness ratios and stacking sequence on the dynamic instability region of GFRP laminated plates is analyzed,the influence of classical laminated plate theory,first-order shear deformation theory and third-order shear deformation theory on the critical frequency of laminated plates is discussed,the mechanism of parametric resonance dynamic instability of rectangular GFRP laminates with four simply supported sides under periodic load is explained.(3)The experimental research on dynamic instability of rectangular GFRP laminated plates with four-edge simply supported.The experimental model of GFRP laminates was designed,manufactured and processed so as to study experimentally on the dynamic stability of GFRP laminates.The time domain curves and the dynamic instability region of parametric resonance of GFRP laminates subjected to periodic loads on opposite sides are obtained through experiments.By comparing the theoretical results with the experimental results,the vibration characteristics and dynamic instability mechanism of GFRP laminates under parametric resonance are revealed,and the theoretical correctness of dynamic instability domain and nonlinear vibration analytic solution of GFRP laminates under different laminates angles is verified.