AbstractControlled rocking systems in a variety of materials have been demonstrated to be highly effective in resisting seismic forces. In a controlled rocking system, uplift of the wall or frame from the foundation is allowed in a way that can localize damage and minimize postearthquake residual drifts. However, the limited inherent damping of the system can lead to excessive displacements. As such, energy dissipation devices (EDDs) have been developed and evaluated to add supplemental damping to the system. These devices have often been embedded within the wall system or have been otherwise unrepairable following seismic events. Therefore, the development of an easily replaceable EDD is expected to maintain the overall performance of controlled rocking systems, while also enhancing their postearthquake repairability. In this respect, steel flexural yielding arms can be an effective EDD for controlled rocking systems. In addition to adding supplemental energy dissipation to the system, the device can eliminate the need for using mechanical stoppers to prevent sliding if the devices are designed to withstand the expected sliding demands. As such, the objective of the current study is to experimentally and numerically investigate the behavior of steel flexural yielding arms with and without axial load demands in order to propose practical design equations for the implementation of these devices. Specifically, the study first presents a description of the experimental program, test setup, instrumentation, and results. Based on these experimental results, a numerical model is developed and validated to evaluate the performance of these devices for a wide range of geometrical configurations. Subsequently, new design equations that account for axial forces are proposed and verified against both experimental and numerical results. Finally, recommendations are presented for the further development of externally attached and replaceable flexural yielding arms for controlled rocking systems.

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