A study on interaction control for seismic response of parallel structures

A structure response control approach which uses controlled interactions between two parallel structures (a primary structure and an auxiliary structure) to reduce the seismic response of the primary structure (P-structure) during earthquake excitation, is proposed. Three strategies of the control approach, including optimal passive control, semi-active control, and active control are examined. The optimum passive-coupling elements between two parallel structures under different circumstances are firstly investigated. Then, emphasis has been placed on the derivation of a simple effective algorithm for semi-active control which guarantees the power absorption of the required control force from the P-structure at every time step. Finally, numerical results in the frequency and time domains are presented to demonstrate the effectiveness of these proposed control strategies. The comparison of the structure response time histories when subjected to El Centro 1940 ground excitation with different control methods also illustrates that the semi-active control based on optimum passive coupling element can achieve improvement in reducing the response of P-structure compared to the passive control and is almost comparable to the active control system with the same degree of magnitude of control force, and that the proposed instantaneous power absorption semi-active control algorithm is always superior to conventional linear control law.