Nonlinear Stability Analysis of Single-layer Honeycomb Spherical Latticed Shells

Abstract

The finite element software ANSYS was used to investigate the nonlinear stability of single-layer spherical latticed shells with hexagonal connection form. Firstly, a reasonable grid layout was determined by analyzing and comparing the stability of two types of honeycomb spherical latticed shells. A large scale parametric analysis was then carried out, including the influences of the span, raise-span ratios, grid size, initial geometric imperfection, asymmetric load distribution, and material nonlinearity on the stability behavior of honeycomb spherical latticed shells. The results show that the grid of typeⅠexhibits better overall stability capacity for two kinds of grid configurations of single-layer honeycomb spherical latticed shells. It is also suggested that the span should not exceed 40 m. The overall stability of the net shell is better and material utilization is higher, when the rise to span ratio is close to 0.25 and the bar length is about 2 meters. Meanwhile, the material nonlinearity has a great effect on the stability of the bearing capacity for single-layer honeycomb spherical latticed shells, and the bearing capacity of latticed shells is decreased by 50%. However, the critical load of latticed shells is reduced by 52% when the initial defects reach 1/150 of the span. Moreover, it is found that the reticulated shells are not sensitive to the asymmetric loads.

Keywords: single-layer honeycomb spherical latticed shells,  stability property,  critical load,  nonlinear analysis