ACTIVE CONTROl OF STRUCTURES

In this study, two different active control design algorithms based on complete state feedback are presented for controlling the structural response when subjecting to ground motion excitation. The active control laws are deduced using the two control algorithms namely; the pole assignment and optimal control techniques. The structural control analyses for a single-story and multi-story structures controlled using active tendons mechanism and modeled to simulate the real operating conditions are perfonned to illustrate the applicabilities and efficiencies of the present methodologies. In addition, the implementation of both control design algorithms is investigated considering a wide range of structural parameters.In addition to studying the tendons mechanism actively, it is also employed passively to clarify the superiority of the active control to the passive one when comparing the response of both cases with that of the case of no control.The equations of motion of the example stmctures are expressed in the state space fonn in the active control case, and their solutions (for both control algoritluns and in the three considered cases named: no control, passive control, and active control) are obtained symbolically to facilitate the execution of different control designs that deal with the most prevailing control problems without wasting long time. Two perfonnance indices are selected as a measure of the active control effect depending on the used design algoritlun. When deducing the control law using the pole assignment technique, the variance ratio between the actively controlled displacement response and the uncontrolled one is used as a perfonnance measure, while a quadratic perfonnance index as a