The Research Of Wind Field And Fluid-Structure Interaction And Fine Identification For Space Structure

The long-span spatial structures (LSS) have been widely used in public buildings. But due to the light mass and the small damp, they are sensitive to wind loads. Therefore, wind loads become one of the principal loads acting on structures in the structural design. Especially for the long-span flexible spatial structures, the fluid-structure Interaction (FSI) must be considered in analysis. How to decide the relative pressure and wind-induced vibration coefficient becomes the focus of the LSS design. The wind field and FSI effects of the LSS as well as the identification of the results are researched in the present dissertation.Combined with the weighted amplitude wave superposition method (WAWS) and auto-regression method (AR), a new mixture simulation technique for wind velocity time history is proposed. The present method significantly reduces time cost for computation with no accuracy lost. The matrix style of Levison-durbin algorithm is put forward and the optimally regression order is judged by the AIC (Akaike information criterion).Based on the Formex algebra and mapping theory, a new method in which the real mesh is mapped by the virtual mesh is presented. The virtual mesh is generated on the virtual regular polygon by Formex algebra, and the real mesh is mapped by the mapping theory. Also, the increment mapping is introduced. Moreover, the quality of the initial mesh and the updated mesh are statistically analyzed. The analysis shows that the good quality mesh system can be obtained by the present method.Based on the traditional Taylor-Galerkin finite element method (FEM), the two-steps and three-steps Taylor-Galerkin finite element formulations are presented. An efficient iterative algorithm is presented for the numerical solution of viscous incompressible Navier-Stokes equations. In order to confirm the properties of the algorithm, the numerical simulations on both plane Poisseuille flow problem and lid-driven cavity flow problem with different Reynolds numbers are carried out. The numerical results indicate that the proposed iterative version can be effectively applied to the simulation of viscous incompressible flows.Based on the theory of the computational wind engineering, the wind field around typical LSS is numerically simulated, with the determination of flow field scale, boundary condition and turbulence model and so on. Comparison of the wind pressure between the numerical simulation and the results from wind tunnel tests of the structural model are mentioned in detail, which indicates wind loads acting on spatial structures obtanined by numerical simulation is feasible and reliable in structural wind-resistant design.In the research for FSI of LSS, A new strategy for data transferring on the FSI interface is put forward. Some concepts describing structural working states such as pre-stress loading state, stable state and coupling state are defined, while the uniform expression for both structural static and dynamic states are developed. The time-history structural dynamic analysis technique, the unilateral coupling process and the coupling interaction process are applied to a series of computation and comparison on the wind effects of some LSSs.Finally, based on the discrete wavelet theory, a series of computation and comparison on the wind-induced vibration responses of LSS and their joint distribution in both time and frequency domains as well as the precision modification for the simulated time history series of wind actions is carried out.