Frequency-domain recursive hybrid GA to parameter identification of structural systems with added-damping-and- stiffness devices

摘要

The method proposed to perform the parametric identification in this paper is the frequency-domain recursive hybrid genetic algorithm. For this method, time histories of the measurement were divided into a series of time intervals, and then the model of equivalent linear system was employed to identify the modal parameters of the system for each time interval. This method was applied to the three-story steel frame structures with and without circular added-damping-and-stiffness devices mounted on the shaking table. The ground motion records used for these structures are time histories of El Centra earthquake adjusted to different intensities. According to the result of identified parameters using the above records, the conclusions can be made as follows: When the PGA value becomes larger: (1) the error index will become larger. (2) the range of the identified modal damping ratios and modal frequencies will become larger. (3) The maximum values of three modal damping ratios will become larger. (4) The minimum value of three modal frequencies will become smaller.