Research Of Static Performance And Stability Of The Radiant Cable Suspendome

The suspendome is a kind of hybrid space structure composed of an upper rigid single-layer lattice shell and a lower flexible tensegrity system, which combines the advantages of the two systems and makes good use of them,so it can make a larger span. The new structural system is of particular stiffness rather than flexible, so the design and construction of it is muck easier, and it has been widely used as structural roof of buildings in recent years.For traditional suspendome, the radial force is a very small part of the force of hoop cables, it is a waste of bearing capacity of hoop cables. During construction stage, the control of prestress is hard, the friction force makes it hard for the hoop cable slipping in the joints and the after stage will cause waste of tension of cables at the previous stage.To reduce these disadvantages, radiant cable suspendome based on single-layer lattice shell is proposed whose cable-strut system is like that of Radiant Beam String Structure, the lower end of the poles is connected by radial cables and inner hoop cable. The purpose of this paper is to study the static performance and the stability of the structure.The analysis of the static performance is carried out for the radiant cable suspendome, the span of whose upper rigid single-layer lattice shell is 60 meters and the rise-span ratio is 0.08. Comparing the results of the hybrid structure with the single-layer lattice shell who has the same geometry parameters, we can found the superiority of the hybrid structure. Next, the study centers on the influence of rise-span ratio and prestress to the force of the members and the deformation of the node.The linear buckling analysis of the hybrid structure is carried out under different rise-span ratios, different prestress level and half-span load. Comparing the eigenvalues of the hybrid structure with the single-layer lattice shell who has the same geometry parameters, we can preliminarily understand the stability of the hybrid structure. At the same time, nonlinear buckling analysis is carried out to study the stability of the hybrid structure under different rise-span ratios, different prestress level, half-span load and the original geometrical imperfection.The results show that the prestressed cables greatly improve the stiffness of the structure, improve the element force status, improve the structure's stability and reduce the structure sensitivity to original geometrical imperfection. To improve the efficiency of the structure, it is unwise to pick single-layer lattice shell as the upper structure, the rise-span ratios should be small so that the cable can bear a greater tension and make full use of the strength of members.