Analytically optimal parameters of supplemental brace-damper system in single-degree-of-freedom structure based on stability maximization criterion

Abstract

In this study, optimal parameters (i.e., optimal additional stiffness ratio α and damping ratio λ) for supplemental brace-damper system in a single-degree-of-freedom (SDOF) structure are analytically derived. Different from the design formulations for supplemental brace-damper system proposed by Londoño, which are essentially fitting formulae through extensive parametric study, analytically optimal parameters for supplemental brace-damper system are derived by combining the research work by Londoño and the stability maximization criterion (SMC). Similar to Optimum Brace Stiffness (OBS) criterion and Optimum Damper Size (ODS) criterion proposed by Londoño, SMC-based OBS criterion and SMC-based ODS criterion are respectively proposed to assure a desired structural performance represented by the targeted overall damping ratio of the considered system. Through numerical study, it is demonstrated that the seismic response of the proposed SMC-based OBS criterion and SMC-based ODS criterion excellently agree with those of the existing OBS criterion and ODS criterion, respectively.