A reduced order model for optimal design of 2-mdof adjacent structures connected by hysteretic dampers

Coupling adjacent structures with supplemental control devices appears to be a useful method to mitigate structural response. In this work, a reduced order model for optimal design of two multi-degree-of-freedom (2-mdof) structures connected by hysteretic dampers is studied. The seismic input is modeled as a Gaussian white-noise stationary stochastic process. Since the passive connection is modeled as a nonlinear hysteretic element, represented by the differential Boue-Wen law, a stochastic linearization technique is applied in order to simplify the problem. The design procedure is based on replacing the 2-mdof system, with a generalized two single-degree-of-freedom (2-sdof) system, by using the principle of virtual displacements; here, each structure is represented by an elementary oscillator interconnected by a hysteretic device. Once the equivalent structural parameters of the generalized 2-sdof system is known, it is possible to carry out the optimal design of the connection by using simple spectra obtained by the authors in a previous work, where the optimal design of a horizontal hysteretic link connecting a 2-sdof system has been studied and solved. Illustrative examples confirm the entire methodology and also verify the effectiveness of hysteretic connection on seismic response. (c) 2007 Elsevier Ltd. All rights reserved.