Fragility Analysis of Structures Incorporating Control Systems

Dynamic hazards present a challenge to the structural designer. Structural control devices offer one effective approach to protect structures during these dynamic hazards. Various classes of control systems have been explored in recent years and have been demonstrated to be effective for reducing structural responses to extreme events. However, the design of advanced damping systems has not been addressed from the broad perspective of performance. Recent interest in Consequence Based Engineering (CBE) has opened an avenue to change that. CBE works to incorporate the predicted performance of a structure as a factor in its design. This research seeks to demonstrate the potential use of the fragility analysis of controlled structures in CBE. Specifically, this study investigates the sensitivity in the fragility of seismically excited buildings to various passive control configurations. A benchmark model of a 20-story structure is employed. Magneto-rheological (MR) dampers, subject to a constant voltage, act as the source of passive damping for these models. Through these studies, we demonstrate the utility of fragility analysis as a design and modeling tool for eventual use as a facet of CBE.