| The building of Fujian Province Earthquake Administration is an 11-story base-isolated building consisting of reinforced concrete frame and shear-wall structural system. There are 52 rubber isolating bearings including 21 natural rubber isolating bearings and 31 lead-rubber isolating bearings between basement floor and first floor. And a strong motion observation array has been installed in the building since August 2005. The records obtained from it, include not only Jiujiang earthquake, Wencheng earthquake, Taidong earthquake and Hualian earthquake and so on, but also vibration during Longwang typhoon. Therefore, the paper primary analyzes 30 earthquake records and Longwang typhoon records, and the main ideas are as follows: Firstly we find out the whole characteristics of isolated building by identifying the most important parameter values (such as predominate frequency, damping ratio and so on) of dynamic property of building, using earthquake records and Longwang typhoon records. And then we build the model of building through two methods, one is ARMA model, the other is three-dimensional model using ETABA Soft. The strongpoint of ARMA model is that the identified parameter is simple and the earthquake record, which it makes use of, is only a few seconds, at the same time it is a real time method of monitoring the vibration of building and facile for engineer. Despite the model of building in Soft can show the whole vibration of building during earthquake, it need more earthquake records to modify the model in Soft. All the studies in the article abide by these ideas, and the main achievements of this study could be summarized as follows:1. Firstly we simply sum up the theory of base-isolated building and then introduce not only the strong motion observation array on the building, but also the situation of seismic records and typhoon records. The methods of analyzing record data are also introduced in the article. All of these works are provided us to analyze the dynamic property of base-isolated building.2. We mainly analyze the dynamic behavior of the isolation building during 30 times earthquake in time domain and frequency domain, and get the statistical results of predominant frequency and damping ratio of building on the basis of the transfer functions. The first-mode predominate frequency of building in NS and EW direction, is about 1.41Hz and 1.58Hz respectively, and the corresponding damping ratio of the building is about percent 3.3 and percent 3.6 respectively. Otherwise we cursorily analyze the torsion characteristic of building during these earthquakes and calculate the torsion frequency at about 2.0Hz. Lastly we appraise the effect of isolation building and draw a conclusion that the seismic response of building is taken to be in linear elasticity and isolation devices of base-isolated building are not effectively performed during these earthquakes.3. The ratiocinated ARMA model based on model analysis method is applied to analyze seismic response of base-isolated building. On the base of ARMA model we make out the transfer function of building compared with Fourier amplitude ratio in frequency domain. This method, which uses only a few seconds seismic record, not only can forecast the whole acceleration in time history, but also have a very high precision. So we can use this method to monitor the vibration of building in real time during earthquake.4. We use ETABS Soft to analyze the dynamic behavior of base-isolated building, inputting seismic records from basement floor, and the result shows that calculated accelerations of building from Soft are very close to actual accelerations from strong motion observation array. Therefore it can be seen that model of building in ETABS Soft is reliable. Furthermore, in order to simulate seismic response of base-isolated building in time history during given earthquake, we modify nonlinear parameter values of lead rubber isolating bearings according to the result of test for structural dynamic property, and input three seismic records obtained from ground of building. It is indicated that earthquake resistance of base-isolated building is well by analyzing calculated peak acceleration of story, story drift and hysteretic curve of lead rubber isolating bearings and so on. At the same time it also shows that model of building needing more strong motion observation to modify is an important and complex job.5. In order to understand the dynamic property of base-isolated building under different dynamic loading, we explain the response of wind-induced records and detailedly compare the response of wind induced to the isolated building during Longwang typhoon with seismic response and the test result of natural excitation to building. And the conclusion, which response of wind-induced is like free vibration with damping and rubber isolating bearings of building mainly consume the energy of wind-induced vibration, is a good cognition to understand the dynamic property of base-isolated building during Longwang typhoon.Finally, the author summarizes the whole work and points out the next study.
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