Seismic response analysis of single-degree-of-freedom yielding structures with fluidic self-centering systems

Analyses of single-degree-of-freedom yielding structures with fluidic self-centering systems are performed for a wide range of parameters and the results are utilized to (a) illustrate the effect of the added fluidic self-centering devices on the behavior of the structural system, and (b) to arrive at conclusions on the appropriate strategy for selection of the structural system and self-centering system properties for design. The results suggest that the primary structural system could be designed for a base shear force not less than 75% of the minimum base shear force prescribed in ASCE 7-2010 for the building exclusive of the self-centering system, and that the drift criteria would be satisfied and the residual drift will be minimal when the fluidic self-centering system is designed for a preload equal to about (or more than) 20% of the story shear yield strength and a viscous damping ratio of at least 10% of critical under elastic frame conditions. Simplified methods of analysis are then presented and verified by comparison to nonlinear response history analysis results. The simplified methods of analysis are found to be reasonably accurate for most practical cases of structural system and self-centering system parameters except for cases of long period structures and when near-fault, pulse-like ground motions are considered.