Research On FE Model Of Tall Building For Wind-induced Serviceability Evaluation

Tall buildings and super tall buildings are more and more popular in recent years. Tall building structures own specialties such as high height, big flexibility and low natural frequencies. To a tall building, wind load is the main lateral load and its natural frequencies of wind are always close to the tall buildings’values, which lead to the structures vibrate apparently and make the people feel uncomfortable, such as nervous and panic, and then lower resident and work quality.Wind-induced serviceability has been an important design index when design a tall building structure. It’s mainly considered to ensure people comfortable based on the structure safety, and it should be evaluated based on the real dynamic states of the structure. A lot of field measurement data indicate that measured dynamic characteristics always have big differences with theoretical values calculated at structures design stage, and as the index of evaluating wind-induced serviceability, structural accelerations calculated are always bigger than measured accelerations after the buildings are completed, and this will result in big errors for serviceability evaluation. The reason maybe is that the calculation models for wind-induced serviceability have big differences with the real structures and can’t reflect the real dynamic states. For wind-induced serviceability evaluation, some research works are carried out to this problem:1. On the basis of referential review of domestic and foreign bibliography, the recent national standards and guidelines on wind-induced vibration serviceability for tall buildings are summarized in a systematic way and some suggestions are provided for these related evaluation guidelines.2. The reasons why tall buildings’calculated dynamic characteristics always have big differences with the measured values are deeply analyzed. Three influence factors including non-structural walls, facing decoration and actual live load are considered on the basis of wind-induced serviceability evaluation, and sophisticated calculation model which is different with the model for structural safety is proposed. Initial FE model of a tall building proximity to the sea in Xiamen is modeled and the three influence factors are then considered respectively in the model. The effects of the three factors for the dynamic characteristics of the structure are analyzed and the dynamic characteristics of final sophisticated calculation model are compared with the full-scale structure modal test under typhoon to verify that the sophisticated calculation model is correct.3. Ten minutes fluctuating along wind speed time series of the building are simulated based on auto-regressive method and are verified. Wind-induced time history analyses are made both on the initial model and the sophisticated calculation model and along wind accelerations are obtained. Wind-induced serviceability of this building is evaluated on the basis of domestic and foreign bibliography and the result is discussed.Finally, based on the summaries and conclusions of all research works, some suggestions and prospect for further researches are put forward.