【摘 要】
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Digital simulation of turbulence wind field is an essential implement to analyze the buffeting behavior of long-span bridges in the time domain.The spectral representation method is widely used in the
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Digital simulation of turbulence wind field is an essential implement to analyze the buffeting behavior of long-span bridges in the time domain.The spectral representation method is widely used in the simulation of stationary turbulence wind field.However,recent field measured wind records during extreme wind events exhibit strong non-stationary features.Hence,it is realistic to perform non-stationary simulation of turbulence wind field of long-span bridges during extreme wind events.In this study,a spectral-representation-based non-stationary process simulation algorithm,which takes advantage of FFT technique,is proposed with the aid of non-negative matrix factorization.In addition,a reasonable scheme is recommended to search initial matrices for non-negative matrix factorization,which guarantees the efficiency and accuracy of the factorization.Once,the decomposed spectrum is factorized,the FFT technique can be utilized to enhance the non-stationary simulation efficiency.The non-stationary turbulence wind field on the deck of a long-span bridge is simulated.Results show that the factorization and simulation agree quite well with the targets.The proposed approach can be used in the simulation of non-stationary turbulence wind field of bridge deck.
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