Experimental Study On The Stability Of New Aluminum Honeycomb Panel Single Layer Combined Reticulated Shell

The stability of the space grid structure has always been considered as one of the most important problems to be solved in this kind of structure.Therefore,the stability of the single-layer reticulated shell structure has always become a hotspot in this field,and the single-layer aluminum alloy Compared to the steel reticulated shell structure is more light and soft,natural stability is more sensitive to the problem.However,most of the research objects of the existing literature are for steel reticulated shells or aluminum alloy reticulated shells.In this paper,the stability of the new single-layer aluminum alloy reticulated reticulated shells with high strength and high strength aluminum alloy honeycomb panels is studied.The results show that the stress behavior,failure mode,failure mechanism and ultimate bearing capacity of this kind of structure are different from the general single layer aluminum alloy reticulated shell.The main contents and conclusions of this paper are as follows:(1)Due to the complexity of the internal structure of the honeycomb panel,the workload of the finite element analysis of the honeycomb panel by physical modeling in the actual project is very large.In addition,the contact between the honeycomb core and the panel irregularities also easily lead to singularity of the stiffness matrix.In order to be able to carry out efficient and reliable calculation and analysis of honeycomb panels,it is necessary to make reasonable simplification and equivalence of honeycomb panels.In this paper,three kinds of equivalent methods,such as sandwich panel theory,honeycomb plate theory and equivalent plate theory,are compared with the finite element analysis results of honeycomb panel actual construction modeling from static deformation and modal frequency,To discuss the advantages and disadvantages of the three types of equivalent methods for the future calculation of the overall model of the honeycomb panel to provide a basis for simplified analysis.The results show that the relative accuracy of honeycomb board is higher,which is more suitable for the simplification of honeycomb board in practical engineering.(2)Single-layer aluminum alloy reticulated shell structure is a defect-sensitive structure,in the stability of the bearing capacity analysis,must consider the impact of defects.The analysis shows that the lowest order buckling modes of the single-layer aluminum alloy reticulated shells do not all reflect the geometric defect distribution of the structures.Therefore,the uniform defect modal method is not the minimum critical load of the structure.(3)Aiming at the experimental model of six single-layer aluminum alloy reticulated shells,the defects of the single-layer aluminum alloy reticulated shell structure and the critical bearing capacity were analyzed by random sampling model based on Gaussian distribution.Stability analysis.The results show that the results of random defect model are in good agreement with the experimental results,and the error is within 10%.In the future analysis of large-scale engineering structure,take 100 samples of random defects to meet the general requirements of the engineering accuracy.(4)The experimental study and the finite element analysis show that the single-layer aluminum alloy reticulated shell structure has improved the mechanical performance due to the honeycomb panel participation structure,and its stable bearing capacity is at least 16%higher than that of the non-reticulated reticulated shell structure.The sensitivity of the defect is smaller than that of the non-plate aluminum alloy reticulated shell.(5)The current limit of the initial geometric imperfection is mainly for the non-plate reticulated shell structure.In order to quantitatively explore the defects of the new single-layer aluminum alloy composite reticulated shells,The results show that when the initial geometric defect value reaches about 3/1000 span,the effect is fully reflected.From the perspective of safety,in the case of the single layer aluminum alloy composite reticulated shell When the structural stability of the bearing capacity analysis,it is recommended to take the maximum defect for the reticulated span of 3/1000.Which provides a reference for the future development of single-layer aluminum alloy composite reticulated shell structure technical specifications of the node installation bias limits.