Application Of Spectral Proper Transformation To Simulation Of Wind Speed

Recent years, the high-level and extra-high buildings of city are getting more and more, these structures is gentle. Therefore the wind-induced response must been brought the attention. In orde to have a comparison to conform to the actual simulation and the estimate wind-induced response to the structure. If the wind response are evaluated in time domain. When using the time domain methods, namely, the Monte Carlo simulation-based methods.Here study on the simulation methods will be addressed. Due to its higher accuracy and robustness, the spectral representation method is more popular in the simulation fields, than the linear filtering (AR, MA, or ARMA) method. Actually, it has become the dominant class of simulation methods. Two types of spectral representation methods exist. One is the original spectral representation method, involving the Cholesky decomposition of spectral density matrixes. The other, the newer one, is named the proper orthogonal decomposition (POD)-based spectral representation method, in which the eigen decomposition From the physical viewpoint, the mechanism of the latter method can be described more meaningfully. And less computational cost will be consumed if the modal truncation of the spectral matrixes is taken for instead of the Cholesky decomposition. Technique is embedded into the POD-based method. In order to provide a guide choice between the two types of spectral representation methods, the truncation accuracy, the stochastic error assessment, the computation efficiency and the improvement of the of wind nalong with the development approaches of the POD-based method deserve special attention. Consequently, study on the following aspects will be included in this dissertation.(1) Concerning how to simulate stochastic wind velocity fields more accurate by using the POD-based spectral representation method. The most widely used is modal superposition method, Simulation formula of POD-based spectral representation method is given at first. Discussion on the effects on the simulation accuracy, induced by involving the modal truncation technique, is carried out. Some characteristics of POD of complex wind field are also investigated. The computational efficiency of modal truncation in both Matlab and Fortran 90 language is compared. It is shown that the POD-based method is more meaningful in physical sense, the error brought by the modal truncation is under the effective control, also have the good enhancement in the counting yield aspect.(2) Wind characteristic which inspires in view of the high-rise construction structure, an elaborate method is proposed to analyze equivalent static wind loading (ESWL). The method includes two processes: the wind-induced respose analysis and the static equivalent treatment. The wind-induced response and ESWL are both analysis, background response is calculated winth quasi-static method; resonant response is analyzed with the Lanczos vector method incorating the Proper Orthogonal Decomposition technique. In the process of static equivalent component is expressed be several several inertia loadings vibration modes. The developed method is employed to analyze wind-induced response and ESWL of the International Trade Operation Center, Xiamen, the results show that the method is effective.(3) The spectral representation method (SRM) based on the proper orthogonal decomposition (POD) is applied to simulation of wind speed. POD based on power spectral density matrix of stochastic vector process is introduced to replace Cholesky decomposition, which resulted in so-called the spectral proper transformation (SPT) technique. In terms of Karman spectrum and Davenport spectrum the wind loading history of the International Trade Operation Center, Xiamen, is simulated. Then, the equivalent static wind loads of the building are calculated using the simulated wind loading. The calculation results are compared with those obtained from the wind tunnel tests and from the Code.