This paper presents a robust static output feedback H(infinity) algorithm for control of hysteretic civil engineering structures subjected to earthquake ground motions. Hysteretic structures present a problem for control design and algorithm development due to changes in the structural parameters during large seismic events. The conventional approach that has been employed in the past is to linearize the structure at the initial equilibrium state, thus ignoring the hysteretic characteristics of the structure when computing the gain matrices. This paper extends the H(infinity) algorithm, which has been developed previously for linear structures, into nonlinear structures using a newly developed procedure that uses stochastic equivalent linearization. In this procedure, the hysteretic parameters are linearized assuming the ground motion to be a filtered white noise using the Kanai-Tajimi power spectral density. The effectiveness of this procedure over the conventional approach is demonstrated by simulation results of a hysteretic single-degree-of-freedom structure subjected to earthquake ground motion. This study also shows the effectiveness of using static output feedback for controlling hysteretic structures. For this case, the control effectiveness is not lost when the measurement of the hysteretic variable is ignored.
Proceedings Title: 7th U.S. National Conf. Earthquake Engineering, Theme: Urban Earthquake Risk, Earthquake Engineering Research Institute (EERI)
Conference Dates: July 21-25, 2002
Conference Title: Proceedings of the 7th U.S. National Conference on Earthquake Engineering
Pub Type: Conferences
Control algorithms, H(infinity), Hysteretic structures, Static output feedback, Stochastic linearization, Structural control