Research on Active Control of Mega-sub Controlled Structure with Dampers Subjected to Seismic Loads

摘要

Mega-sub controlled structure (MSCS) is a new form of super tall buildings associated with excellent earthquake-resistant capability. However, As the dynamic behavior and response characteristics of a practical MSCS with active control is different from the MSCS which is only installed additional dampers, it is necessary to further investigate its control mechanism and control effectiveness. In this paper, a new control method is proposed which employ active control and passive dampers together to form a huge control system based on the particular conformation characteristic of MSCS. Active control, for mega-sub controlled structure subjected to seismic loads is investigated based on LQR algorithm. Dynamic equation and method to assembling parameter matrixes for the meg-sub controlled structure under seismic ground motions are presented. Moreover, the additional damping ratio, the weight matrixes are defined and a study of the two parameters that influences the response control effectiveness, control force and dynamic characteristic of the MSCS is discussed; the regulative relationship between additional damping ratio and active control parameter is also analyzed. The result indicates that the new structure employing active control can further reduce the responses of this building. With control parameter changes, the effectiveness that influences the dynamic responses of mega-frame and substructure by additional damping value is different. Therefore, when active control is adopted on MSCS, it's necessary to adjust the damping value according to the size of the matrix to obtain the optimal control performance and active control force synthetically. This lay a foundation for further studying seismic performance and design of steel mega frame structures.