Determination of prestressing levels for cable trusses as a function of their stability
The stability of prestressed cable trusses subjected to static and dynamic loads is analysed in the paper. The stiffness of the elastic cable truss system was varied by changing the prestressing force. Modelling results for different levels of tension show that, in terms of satisfying dynamic resistance conditions, a much greater tensile force is required for cable grids with diagonal members, compared to those with vertical rods. The conclusions derived constitute recommendations for the use of calculation methods, as well as for the determination of prestressing forces under which stability criteria are fulfilled.
Proper Shape Analysis of Spatial Cable-Frames
Proper shape analysis of spatial cable-frames for purpose of preliminary design is discussed in this paper. By functional analysis or using the equilibrium equation group directly, curve functions of the upper and lower chord cables can be built. When only the self-equilibrated internal force is considered in the system without external loads and self-weights of members, optimal curve shape of chord cables are straight lines. The numerical algorithm by bonding linear deduction method and dynamic relaxation method for wind load adaptive shape analysis of spatial cable frames is put forward. The adaptive shape determination of spatial cable frames with averaged wind load of a practical stadium canopy is tried.
Representation of systems disturbed by wide band noise
In this paper, a method of handling and working with wide band noise is developed. We represent wide band noise as a distributed delay of white noise and use it to reduce a nonlinear system disturbed by wide band noise to a nonlinear system disturbed by white noise. An application of this reduction to a nonlinear filtering problem under a wide band noise disturbance is discussed.