Study On Dynamic Stability Of Schwedler Single-layer Spherical Reticulated Shells

Based on the time-history analysis method, the dynamic stability of Schwedler single-layer spherical reticulated shells is studied with the finite element analysis software ANSYS in this dissertation, and the main contents and achievements are shown as follows:1. It is researched that the geometry specialty of Schwedler single-layer spherical reticulated shells, then the corresponding macro is worked out and the automatic building model of single-layer reticulated shells is realized.2. The free vibration characteristic of Schwedler single-layer spherical reticulated shells is analyzed taking into account the influence of many kinds of factors such as the span, the ratio of rise to span, the roof loads,the cross-sectional areas of members, the condition of supports and so on, then the first frequency practicality designing chart is drawn.3. The dynamic stability of Schwedler single-layer spherical reticulated shells under the simple loads is analyzed, when investigating the stability of the shells under step loads, the initial geometric imperfection and the structural damping are taken into account. The dynamic stability of shells under triangular loads is analyzed taking into account the influence of the different duration.Harmonic response on the shells is analyzed to determine the resonant frequency of the shells, and the dynamic stabilities of the resonance region and off resonance region of shells under harmonic loads are analyzed respectively.4. The dynamic stability of Schwedler single-layer spherical reticulated shells under the seismic loads is analyzed, the factors, which affect the response behaviors, such as the input dimensions of the seismic loads, the material nonlinearity, the structural damping, the initial geometric imperfection, the cross-sectional areas of members, the ratios of rise to span, the roof loads, the condition of supports and the different earthquake waves, are taken into account.The research results of this dissertation are good references for actual project designing as well as a theoretical foundation to compile the relevant design criterion.