# The Stability of New Single-Layer Combined Lattice Shell Based on Aluminum Alloy Honeycomb Panels
## 1 Introduction  
A honeycomb sandwich structure is a typical lightweight and high-strength biomimetic structure [1; 2; 3; 4]. Based on the characteristics of a lightweight beetle forewing structure [5; 6], [PERSON] et al. developed an integrated biomimetic honeycomb sandwich structure [7; 8], which has advantages, such as cementing free, single cast forming, and excellent mechanical properties [6; 9]. Currently, this plate is composed of reinforced basalt fibre epoxy resin composite material; the thickness of the honeycomb wall is approximately 2 mm [10]. By comparison, the thickness of the honeycomb core wall of the aluminium alloy honeycomb sandwich structure is approximately 0.05 mm, which is approximately 1/40 of the former. The latter is more suitable for a large span spatial structure, which is especially sensitive to dead weight [11; 12; 13]. To improve the overall stability and ultimate bearing capacity of single-layer aluminum alloy lattice shells, in this paper, the authors propose a new spatial structure system made from an aluminum alloy. The system consists of lightweight high-strength aluminum alloy honeycomb panels that are reliably connected to the single-layer aluminum alloy lattice shell by special connecting parts. This forms a new type of single-layer aluminum alloy combined lattice shell structure. In this structure, which is referred to as a new spatial combined lattice shell (NSCLS), the plates and rods support and reinforce each other [14]. Our previous studies [15; 16; 17] showed that the new spatial structure has characteristics, such as a large span, light dead weight, and high total rigidity. Because the honeycomb panels support and reinforce the structure, the overall stiffness and stable bearing capacity of the NSCLS structure are obviously higher than those of a single-layer aluminum alloy lattice shell structure with the same span. Under the same load conditions,the new system can sustain a structure with a larger span. For these reasons, it has good application prospects (Figure 1). In the study of single-layer aluminum alloy lattice shells, [PERSON] et al. [18] analyzed with nonlinear finite method to clarify the stability performance of aluminum alloy single-layer latticed shell. The suggested values of rise/span ratio and initial imperfection were presented. The influencing coefficients of initial imperfection and material nonlinearity on stability bearing capacity were obtained. [PERSON] et al. [19] tested four single-layer aluminum alloy spherical lattices using reduced-scale models. They studied the effects of three factors (high span ratio, load distribution pattern, and grid form) on the steady bearing capacity. The bearing capacity of the lattice shell with a mixed quadrilateral and triangular mesh was close to that of the one with an entirely triangular mesh. The influence of the nodal domain was taken into account in the finite element analysis [20], [PERSON] et al. [21] devoted to investigate the resistance of aluminum alloy gusset joint plates. It was found that the main collapse modes of AAG joint plates include the block tearing of top plates and the local buckling of bottom plates. [PERSON] et al. [22] analyzed the performance of aluminum alloy single-layer latticed shell by considering the combination of dead loads, live loads, snow load, wind load, temperature effect, and other seismic dynamic loads. With the geometrical nonlinear finite element method, the stability coefficient and the weak parts of the structure were obtained when considering initial imperfections and material nonlinear. [PERSON] et al. [23] used a numerical simulation to analyze the geometric nonlinear stability of an aluminum alloy lattice shell. They discussed the influence of the vector-to-span ratio, the load distribution, and the supporting condition on the stable bearing capacity of the lattice shell. In the study of the honeycomb structure's stability, [PERSON] and [PERSON] [24] considered the shear deformation of the panel and the core honeycomb layer.