Analytical Analysis Method And Application Of In-plane Equivalent Mechanical Properties Of Honeycomb Structures

Honeycomb structure is not only beautiful structure,symmetrical shape,is the best structure to cover two-dimensional plane,but also has large specific strength,high specific stiffness,good heat insulation and many other excellent performance,so honeycomb structure is widely used in construction,transportation,mechanical engineering,aerospace and other fields.Although the honeycomb structure has advantages in many aspects,but in the process of engineering design and analysis,usually experiment method is time-consuming and not the economy,the finite element method in the process of structure system modeling,model scale and detailed modeling greatly increase the difficulty,make the calculation efficiency decreased significantly,complicated structure and the boundary conditions at the same time,also makes the model has some limitations.Therefore,in this paper,the discontinuous structure is equivalent replaced by continuous orthogonal anisotropy body,and the material equivalent model is used to simulate the structure,so as to reduce the modeling difficulty and improve the computational efficiency.In this paper,the star honeycomb structure and accordion honeycomb structure optimized by the topology of traditional honeycomb structure are studied.The main contents of the study are as follows:（1）The structural model of star honeycomb structure is established,and its representative cells are selected for analysis.Firstly,the theoretical model of star honeycomb structure is established through the decoupling equation using the energy method.Secondly,the finite element model is established to verify the theoretical model,and the finite element model is analyzed.Finally,the effect of main structural parameters on the equivalent mechanical properties of star honeycomb structures in plane is further studied by parameter analysis,and a calculation method which can reflect the equivalent mechanical properties of star honeycomb structures with the same negative Poisson’s ratio is established.（2）For the representative cell of accordion honeycomb structure,the stress characteristics of the cell in different directions were firstly studied.By symmetry of structure and load,the cell was simplified as a inclined panel with boundary constraints.The equivalent material parameters of the structure were decoupled by energy method and the theoretical model was established.Secondly,a finite element model of accordion honeycomb structure was established to verify the theoretical model,and the structural displacement,stress and strain were analyzed through the finite element model,and the existence of zero Poisson’s ratio effect was verified.Finally,the effects of the main structural parameters on the equivalent mechanical properties of the hand-wind honeycomb structure were studied,and a linear analysis method was established to reflect the equivalent mechanical properties of the same type of zero-Poisson ratio accordion honeycomb structure.（3）For accordion honeycomb structure at the large deformation stage,first by deformation harmony and balance condition of nonlinear algebraic equations are established,the second use and poor product formula,the first kind of complete elliptic integrals and the first kind of incomplete elliptic integral under the condition of large deformation of inclined wall plate bending deformation of the elastic and plastic analysis,According to the analysis results,the equivalent stress-strain relationship is established and the nonlinear equivalent material parameters are obtained.According to the nonlinear equivalent material parameters and linear equivalent material parameters,the nonlinear correction factor is obtained.According to the nonlinear correction factor and linear equivalent material parameters,the influence of each parameter on the nonlinear correction factor of accordion structure is analyzed according to the main structural parameters（length,Angle）and material parameters（yield stress）.A nonlinear analysis method for the same type of zero-Poisson ratio accordion honeycomb structure is established.