Research On Wind-induced Vibration Time-history Analysis Of Tall Building Structure

With the development of social economy and technology, the tall building structure is become more and more high, as well as those with complicated shapes and energy dissipation systems, which bring new problems and concerns for structural wind engineering of tall building structures. Wind load is one of the important dynamic loads acted on these kinds of tall and slender structures, it may even play decisive role at times. There are two main theories in wind-induced vibration analysis: frequency domain analysis and time domain analysis. The latter method is further studied in this paper based on extensive foreign and domestic existing research achievements. And the contents are as follows:1) Numerical simulation of wind speed and wind vibration time-history analysis based on numerical simulation. In numerical simulation of wind speed, fluctuating wind speed time-history is assumed to be a stationary Gaussian random process and Davenport spectra is adopted as wind speed spectra. Auto-regressive method is used to simulate the random wind dynamic loads based on object-oriented programming language. Program modules of pre-post process with graphs and interface with finite element modeling (FEM) program are also written in. It makes wind-induced vibration time-history analysis for tall building structure a convenient process. Wind vibration time-history analysis based on numerical simulation of 7 typical tall building structures is carried out in this paper. The results are compared with the results calculated by code method, the comparison show that the results of story shears, displacement and along-wind top acceleration march well except across-wind top acceleration. The validity and accuracy of this method are verified and a reasonable valuation method for wind-induced vibration time-history analysis is proposed in this paper.2) Wind vibration time-history analysis based on wind tunnel test data. Take a certain twin towers as an engineering project. Wind-induced vibration time-history analysis for the origin structure is realized by wind load time-history transformed by wind pressure time-history gained in the wind tunnel test. The results gained by the time domain method mentioned above are compared with the results gained by the frequency domain method and the code method. The comparisons show that, the results of 3 methods march well in along-wind direction, the results of time-history analysis and frequency domain analysis march well in across-wind direction. And the validity of time-history analysis based on wind pressure time-history gained in wind tunnel test is confirmed. Wind-induced vibration dynamic characteristic of the skyscraper under different wind directions and consideration of mutual interference of twin towers is also studied in this paper. Wind vibration analysis based on numerical simulation mentioned above checked by the results gained time-history analysis based on wind tunnel test data is applied in this paper. And the comparison of 2 methods show that, except across-wind top acceleration, the results of story shears, displacement and along-wind top acceleration march well.3) Wind vibration control analysis based on wind tunnel test data. Take a long-span connected tall building structure with vicious dampers as an engineering project. Wind-induced vibration time-history analysis for the origin structure with and with out vicious dampers is realized by wind load time-history transformed by wind pressure time-history gained in the wind tunnel test. The results show that energy of fluctuate wind can be well dissipated by vicious dampers. Structural interforce, deformation, top acceleration can have a certain decrease, and the control effect of acceleration is more effective than the two others. Wind-induced vibration dynamic characteristic of the structure with complicated structural shape and vicious dampers under different wind directions is studied. And the effectiveness of vicious dampers for structure vibration control on structural internal force, deformation and comfort problem is confirmed.