利用ARX模型识别土-结构体系的低阶模态频率和阻尼

利用美国Alaska-14层的办公大楼及周围场地上记录到的地震动，对此结构进行了低阶模态频率和阻尼的识别。和考虑土-结构动力相互作用后的土-结体系的低阶模态的频率和阻尼的识别。提供了一种ARX参数模型辨识方法，并与非参数模型辨识比较分析，发现两种模型得到的低阶模态频率和阻尼基本一致，但在高阶模态上会出现明显的差异。通过分析还发现考虑土-结相互作用后，体系的传递函数幅值有所降低。并编制了相应的Matlab计算程序。

Identification of first-modal frequency and damping in soil-structure interaction (SSI) system

The first-modal frequency and damping of a building are identified by using the earthquake records on the building and on related free-field in Alaska, USA. The non-parameter model and ARX parameter model of the structure are used in the identification system, and soil-structure interaction system and structure -system are both identified. By comparing the results obtained from the identification system with the results obtained from the both model is identical in low-frequencies, and but the amplitude of transfer function obtained from SSI system is smaller than from structure system itself, especially in high-frequencies. All these computations are realized on the Matlab platform.