Abstract:It is an effective solution to install MR damper on adjacent structure to mitigate seismic responses and prevent pounding during earthquake. In this paper, trust-region based instantaneous optimal semi-active control algorithm (TIOC) is introduced to earthquake excited adjacent structure installed with MR damper. Based on the equation of motion, the optimization equations of the semi-active control problem are first proposed. And then TIOC optimization problem subjected to a bound constraint is deduced, and optimal semi-active control forces are calculated at every time step. Finally, simulation is carried on adjacent structures installed with MR dampers applying TIOC algorithm. The results show that the seismic responses of adjacent structures can be reduced effectively; compared with Clipped-optimal control algorithm, TIOC algorithm is more capable of controlling the relative displacement between the structures; it is found that TIOC algorithm has great adaptability, the controller’s behavior can be significantly changed with the objective function and thus should be decided carefully.