Geometrically nonlinear wind-induced responses of prestressed cable-suspended roof

Abstract

This paper presents three schemes to calculate geometrically nonlinear wind-induced responses (GNL-WIRs) of a prestressed cable-suspended roof, and intends to lay a solid foundation for the coming equivalent static wind loads. The three schemes and their associated finite element theory (FET) are first introduced. Based on a wind tunnel test, a large number of computations about the different GNL-WIRs yielded by the parameter changes are then performed. The results demonstrate that the GNL-WIRs with complicated proportions and distributions are broadband processes, in which the lower-order frequencies are suggested to be totally embraced. The WIRs have different nonlinear degrees and wind sensitivities, based on which the structural nonlinearities behave dissimilarly and tend to be moresusceptible to prestress, and the structure shows wind sensitivity in view of the displacements. In the displacement PSDs, there are no resonant peaks at the structural basic frequencies when the structure is nonlinear. At the same time, although different parameters give diverse accuracies and PSDs to schemes 2 and 3 in the WIRs, scheme 2, compared with scheme 3, is closer to scheme 1 only for the weak nonlinearity.