The Stability Study Of The Roof-structure In Reversing V Beam String Structure

A reversing v Beam String Structure is composed of bend repelling component with great intensity (beam) and flexible component with high intensity (cable) along with the stay bar between them. By pre-stressing the flexible components, it makes the inter-connective components be a self balanced system with global intensity. The reversing v Beam String Structure generally used in space structure with large span. Since its higher arch, it has the same problem of destabilization under stress just like the normal steel structure. In case os the structure being destabilization, it will result in economic loss or even hurt people. So that it is necessary to investigate the static stability and dynamical stability of the reversing v Beam String Structure, it has important realistic significance.The main research of this paper includes the static elastic-plastic stability analysis of a single reversing v Beam String Structure with equal load in the entire span and the influence of each factor to its stability. Also the static stability and dynamical stability of the roof-structure with reversing v Beam String Structure is analyzed.First of all, the static elastic-plastic stability analysis of a single reversing v Beam String Structure with equal load in the entire span is studied; its destabilization and breakage are tracked in all the process by arc length method; the under stress performance and breakage mechanism are opened out.Secondly, the comparison analysis of the static stability of a single reversing v Beam String Structure is processed using a lot of models which contain different center cable lengths to arc height ratios (h/H), different arc height to span ratios (H/L), different pre-stressing and bearing conditions. Then we got that h/H,H/L and bearing conditions have large influence to the static stability of this structure, but the pre-stressing of the cable affects little to the static stability of this structure.Thirdly, the static stability of the roof-structure of a science museum's 40 reversing v Beam String Structures and sustainers is analyzed. Every reversing v Beam String Structure is connected to be a system using sustainers, and cooperates with each other. The circle sustainer changes the stress transfer of a single Beam String Structure, and makes the under stress and distortion change a lot.Fourthly, the comparative analysis of the displacement to time responses are carried through under the effect of the three kinds of seismic waves(1940's EI Centro wave, 1952's Taft wave and local field wave ) on the roof-structure with reversing v Beam String Structure, discovering that the EI Centro wave is the worst seismic wave to the displacement responses of this structure.Finally, the dynamical stability analysis of the roof-structure with reversing v Beam String Structure under the effect of the EI Centro waves are carried through on x, y, z and all of the three axes. For the effect of the horizontal wave, the dynamical destabilization of the roof-structure mainly parallels to the Beam String Structure in the input direction of the seismic waves, after the material becomes plastic property, the roof-structure occurs large apophysis and sunken and makes the whole roof-structure lose its stability. For the effect of the vertical wave, the Beam String Structure with lesser span occurs largish distortion and making the whole roof-structure lose its stability. The effect of the three directions EI Centro waves act on the roof-structure is also studied. Under this condition, when it loses the stability, a large number of ridges of Beam String Structures all become plastic property.