Configuration, Static and Stability Analysis of Torsional Lattice Shell Composed of Sixbar Tetrahedral Units

Abstract:

A new type of torsional lattice shell composed of sixbar tetrahedral units is proposed in this paper. The configuration analysis shows that its form is simple because of the comparatively fewer members and the higher evacuation ratio. The shell has advantages both of singlelayer and doublelayer shells. Both static and stability analyses of the lattice shell with semirigid joints are carried out in this paper. It turns out that the upper chord members all carry loads in compression while the lower chord members all carry loads in tension. The web members are mainly in tension except for the ones close to the boundary. The members can be designed using similar sections due to the little variation between their internal forces, which makes the structure design convenient and helps improve the material using efficiency. The integral rigidity of the structure is good; its nonlinear stability coefficient is just a little smaller than its eigenvalue of the first mode. The steel consumption is comparatively small. This new structure can be applied in single torsional shells with two evacuation schemes, three kinds of torsional shells composed of four single shells and one kind of torsional shells composed of two single shells.

Key words:six-bar tetrahedral units; torsional lattice shell composed of six-bar tetrahedral units; single torsional shell with semirigid joints; structural form; static analysis; stability behavior; steel consumption