Department of Civil Engineering, Science and Research Branch, Islamic Azad University (IAU), Tehran, Iran
Structural Dynamics Department, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran
In this paper a time varying optimal control algorithm (β-Method) is proposed to control building responses, against environmental earthquake excitations. The proposed method is presented through defining a rational relation between the state variables of a structure with active and passive control systems with identical mechanisms. This procedure results in a time varying gain matrix with adaptable ability to external excitation in order to decrease the extra need for maximum and/or total control force. Performance of the proposed method is examined by applying it to an eight-story shear type building subjected to various ground accelerations. Numerical results indicate that the proposed algorithm in some cases reduces the power consumption demand significantly without any reduction in control system performances in comparison with the classical closed loop optimal control method and acts similar in the worst case.