A Decomposition Method Of Non-stationary Wind Effects Including Three Components And Analysis Of Wind Effects Of Membrane Structure By Full-scale Measurement

Wind effect shows obvious non-stationarity under gust and typhoon etc.How to describe non-stationary wind model and wind effect characteristics is a difficult issue and focus in current research.Based on existing methods to express wind speed,a new decomposition method of non-stationary wind speed including three components is established in this paper to analyze the characteristic of various components by full-scale measurments.In addition,wind effects of membrane structure was measured,non-stationary characteristics of measured wind effects were analyzed and structural modelparameters were identified.The main works are included as follows:(1)Quantitative evaluation method of non-stationary wind speed is extended to wind effect to study the contribution of varied periodic components of the signal to the overall signal,and to evaluate the effect of different methods transforming non-stationary signal to sationary signal.The results show that the non-stationary degree of the components with long periods is more obvious in the wind effects.The non-stationary degree of the signal can be better reduced when the normlized function of time-varying standard deviation is employed as the modulation function.(2)Based on the quantitative method of non-stationary wind effect,a three-component model to decompose the non-stationary wind was proposed.The characteristic and correlation among each component are analyzed for the measured wind speed data.Consequently,the stationary fluctuation wind speed obtained with above decomposition method shows weak correlation with other components and time-varying standard deviation are correlated strongly with slowly varying wind speed.(3)Wind effects of the umbrella membrane structure was measured by full-scale measurement,the non-stationary characteristic of wind-induced response of the membrane structure were analyzed and the structural membrane parameters were identified.The nonlinear effects of structural damping were analyzed.And the damping ratio trends to increase with the increase of amplitude.