Analysis Of Free Vibration Characteristics, Seismic Characteristics And Wind-induced Dynamic Response Of The Radiate Spatial Truss String Structure

A new type of self-balance structure—The radiate spatial truss string structure, which is composed of truss, struts and cable are presented in this paper. The stress of its component is succinct and definite. Tension and compression members are collaborative well and made full use of advantage of different materials. It is typical hybrid system with the combination of rigid and flexibility in large span structures. Because of the reasonable mechanical performance of this structure and the wide developmental space of the large span structure in our country, it is sure that this structure will be used more and more widely.Based on the existing research on BSS (Beam string structure) and the prestressed spatial truss string structure, and taken use of the large common finite element program ANSYS, the dynamic properties of the radiate spatial truss string structure were studied as follows:(1) Taking use of the APDL (ANSYS Parametric Design Language) in ANSYS, this paper is developed the spatial parametric program for the model building and the solution of this structure, which is settled firm base of the intensive study of the dynamic mechanical performance and the optimization design of the structure.(2) Taking structure model and subspace iteration method of software ANSYS, the free vibration characteristics of the radiate truss string structure were analysed systematically. Though a large amount of the different parameters analysis such as the rise-span radio, the sag-span radio, the number of radiate truss, the number of struts, the prestress of radiate string, the prestress of round string etc, the influence of several parameters on the free vibration characteristics of radiate truss string structure were obtained as well as the pattern of free vibration.(3) Large space radiate spatial truss string structure responses to uniform excitation of earthquake were discussed. Though analysis of the different parameters, for example, the rise-span radio, sag-span radio, the number of struts, the prestress of radiate string etc, three-dimension excitation effect were introduced in this structure. Though comparing the structures of properties and the seismic responses, the results from the analysis is supplied some useable conclusion for us to make further researches as well as practices, which may be a reference for project design.(4) In this paper, Auto-Regressive (AR) model is employed to simulate wind speed time series, which is based on the natural wind properties and the correlativity of nodal wind. It is rapid implementation method by programming Matlab. The wind load is imposed on the structure and wind-induced dynamic properties of structure were discussed though different parameters, such as the speed of wind, the rise-span radio, the number of struts and the prestress of radiate string etc, which is settled the base for the intensive study of the structural dynamic behavior.