Nonlinear Stability Analysis Of Single-layer Honeycomb Spherical Latticed Shells

With the continuous development of the society, people demand not only the span and the height of the structure, but also more and more people pursuit the novel structure, so a variety of new forms of space structure gradually are developed. In this paper, relative to previous spherical reticulated shell, we study a new structure, the honeycomb type spherical reticulated shell, it has very little bar specification, through the reasonable modeling has resulted in a bar structure(with the exception of linked to support bar) exactly equal, such as the same bar make industrial production is very convenient, and it can brought great convenience for construction, so it has great value in research.At first, the stability of the two types of honeycomb type grid performance are analyzed, it determines a more reasonable type of grid, and then a large scale parameter analysis has been researched, such as the span, the rise-span ratio, the initial defect, the net shell sparse degree, the asymmetric load distr ibution, and the material nonlinearity influence on the stability of the reticulated shell, Finally, seven kinds of strengthening scheme of net shell are put forward and compared to select the better strengthening scheme. the results are shown below.(1)Between the two bar arrangement of the honeycomb type spherical reticulated shell structure, with the overall stability of the grid type Ⅰ performance is good, compared with the grid type Ⅱ, the grid type Ⅰ have better ultimate bearing capacity and better ductility.(2)It has good regularity that rise-span ratio on the stability of single-layer cellular type spherical reticulated shell effect significantly, considering the factors of stability of the reticulated shell and material utilization, we sugge st that the rise-span ratio is around 0.25.(3)The grid sparse degree of honeycomb type spherical reticulated shell has great influence on ultimate bearing capacity, we analyze the suitable bar length of the honeycomb type spherical reticulated shell, it will have higher bearing capacity and better material utilization, so it suggested that bar length is about 2 meters.(4)The single layer honeycomb spherical latticed shells are sensitive to the initial defects, in the abstract, the maximum defects of the span is 1/150, the ultimate bearing capacity of the actual net can account for 50% of the ultimate bearing capacity of the ideal net, so in the actual situation, we should consider the influence of the initial defects.(5)The geometrical nonlinearity and material nonlinearity have a huge impact on the ultimate bearing capacity, so in the practical design of the reticulated shell of the engineering, we should also consider the effect of geometrical nonlinearity and the material nonlinearity.(6)The effect that the asymmetric distribution of load on the ultimate bearing capacity of honeycomb spherical latticed shells is not significant.