Dynamic Behavior Analysis Of Reinforced Functionally Graded Laminated Doubly Curved Plates

Functional gradient material is a kind of multi-component composite with high performance.Its material components are in a continuous gradual distribution state along with the spatial position at the micro level.Therefore,it can integrate the advantages of various materials by adjusting the component parameters according to the use requirements,so as to achieve the performance transformation of functional gradient material itself.Due to its flexible and diverse controllable characteristics and excellent performance of composite integration,functional gradient materials have been deeply integrated with the operation and development of aerospace,engineering equipment,nuclear power generation,civil engineering and many other industrial fields.Based on the application needs of multi physical fields and extreme load environments,various new hybrid functional gradient materials and structures have been studied to meet the rigorous mechanical performance requirements under multi field coupling.Based on the above research background,this paper has carried out in-depth analysis and research on the dynamic behavior of functionally graded laminated doubly curved plate structures with performance enhancement effect in the thermal environment.The main research and innovation contents are as follows:The impact dynamic mechanical model of functionally graded laminated doubly curved plates under the support of variable cross-section stiffeners is established,the quantitative relationship between the performance of functionally graded laminated composites,multiple geometrically nonlinear superimposed structures and impact response under the influence of thermal factors is deconstructed,the impact dynamics related research of nonlinear stiffened plate and shell structures is expanded,and an efficient theoretical analysis scheme is presented to solve similar thermoelastic dynamics problems.The results show that the displacement(stress)amplitude of the doubly curved plate is positively related to the impact velocity,but negatively related to the thickness of the doubly curved plate(the section stiffness and arrangement density of the variable section stiffeners);With the increase of temperature,the amplitude of lateral displacement increases,which weakens the impact resistance of the structure;With the help of curvature parameter adjustment and material composition replacement of doubly curved plates,the overall stiffness performance of the structure can be effectively changed.A mechanical model of functional gradient laminated doubly curved plate with Winkler Pasternak elastic foundation reinforcement and inhomogeneous pore effect is constructed,and the dynamic response of the structure under multi-point explosion impact is studied and analyzed,and the accurate quantitative design of corresponding structural parameters is realized.The results show that the strength of structural stiffness weakening is not the same when the pore distribution is under the same analysis conditions,and the homogeneous pore material structure gives a relatively robust impact response performance;The adjustment and matching of structural material parameters and elastic substrate parameters can further enhance the impact resistance of the structure;The variability of non-uniform temperature field affects the displacement response(stiffness)state at different positions of the structure,and the overall trend is that temperature rise promotes the increase of displacement amplitude.A mechanical model of a folded piezoelectric hybrid functionally gradient laminated doubly curved plate is proposed.The degree of folding is quantified by geometric parameters.The mathematical quantitative correlation between the physical phenomena of folding and the properties of piezoelectric hybrid functionally gradient materials is established,and the influence of moving loads on the dynamic behavior of piezoelectric reinforced structures is revealed.It is proved that the moving load type and action path can affect the response performance of the laminated doubly curved plate,which has specific response characteristics,and the displacement(stress)response amplitude is positively related to the load strength;Crease sharpening weakens the structural stiffness and produces greater deformation;The dynamic response of structures can be improved by adjusting the parameters of functionally graded materials to enhance the structural stiffness and mitigate the dynamic load impact.The mechanical model of laminated doubly curved plates with CNT(Carbon Nanotube)reinforced FGM lattice sandwich is established,and the effects of thermal environment,CNT distribution,laminated sandwich design and other factors on the nonlinear vibration response of laminated doubly curved plates are studied.The research shows that CNTs can effectively enhance the stiffness of the laminated doubly curved plate structure,and symmetrical distributions of CNTs can greatly improve the structural stiffness;the lattice sandwich can effectively reduce the equivalent density of the structure and realize the lightweight of the structure.The vibration characteristics of the structure can be effectively improved by adjusting the geometric parameters of the laminated doubly curved plate;Temperature rise can weaken the structural stiffness and affect the vibration characteristics,so material characteristics and structural design must be strengthened to cope with severe temperature changes.A graphene nanoplatelet reinforced functionally gradient material model was established.Considering the aggregation effect under the influence of the distribution form and aggregation form of GNP(Graphene Nanoplatelet),the quantitative relationship between the aggregation characteristic parameters of GNP and the properties of the enhanced functionally gradient material was obtained.The dynamic performance optimization of GNP reinforced functionally gradient laminated doubly curved plate structure was realized by particle swarm optimization(PSO)algorithm.The results show that GNP enhancement can significantly improve the vibration response of the structure;The difference of the geometrical size of GNP reinforcement is too large,which is not conducive to the stability of the overall material properties.The increase of the aggregate volume parameter of GNP reinforcement can enhance the overall material properties,and the increase of the component parameters of GNP reinforcement in the aggregate will weaken the overall material properties;The application of honeycomb sandwich structure is helpful to the lightweight design of laminated doubly curved plates.The integrated optimization calculation of materials and structures can obtain the parameter combination of ideal structural performance.