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A new friction device using band brake technology, termed the Banded Rotary Friction Damper (BRFD), has been fabricated at the NHERI Lehigh Experimental Facility. The damping mechanism is based on band brake technology and leverages a self-energizing mechanism to produce large damping forces with low input energy. The device is a second-generation BRFD, where the friction mechanism is achieved using two electric actuators. The BRFD generates a damping force as a function of the input force provided by the electric actuators, where the ratio of BRFD force output-to-electric actuator force input is equal to about 112. The paper presents the results of a study using real-time hybrid simulations (RTHS) to investigate the performance of the BRFD’s in mitigating seismic hazards of a two-story reinforced concrete building. The building has two and three special moment resisting frames (SMRFs) in the east-west and north-south directions, respectively. In order to perform the RTHS, the north south SMRF is considered and the BRFD along with a parallel elastic member is used as a base isolation system to mitigate the effects of earthquake hazards by reducing story drift and floor accelerations of the structure. For the RTHS the building and the elastic component of the isolator are part of the analytical substructure while the experimental substructure is comprised of the BRFD. The response of the structure is investigated involving six Maximum Considered Earthquake (MCE) hazard level events that includes three near-field and three far-field ground motions. The explicit, unconditionally stable dissipative Modified KR-α integration algorithm is used to accurately integrate the equations of motion during the RTHS. The model for the reinforced concrete building is created using explicit non-linear force-based fiber elements to discretely model each member of the structure. First, the details of the prototype of the BRFD are presented. Second, the details of the isolator system consisting of a linear spring element and the BRFD are discussed. Finally, the details of the RTHS study and the results are presented. The building’s inter-story peak and residual story drift from base-isolated and fixed-based conditions are compared. Results show that the proposed isolator system produces a significant reduction in both maximum inter-story drift and residual drift, and reduces the damage developed in the structure during the MCE. 

Drywall partition walls (DPW) could considerably affect the seismic resilience of tall cross-laminated timber (CLT) buildings due to cost and building downtime associated with repair. These drift sensitive components are susceptible to damage at low shaking intensities, and thus controlling or eliminating such damage in low to moderate earthquakes is key to seismic resilience. Conversely, post-tensioned CLT rocking walls have been shown to be a resilient lateral load resistant system for tall CLT building in high seismic areas. A series of tests will be performed at the NHERI Lehigh EF to compare the performance of DPWs with conventional slip-track detailing and alternative telescoping slip-track detailing (track-within-a-track deflection assembly), and to evaluate different approaches for minimizing damage at the wall intersections through the use of gaps. Moreover, a configuration is examined with partition wall encapsulating the rocking wall for fire protection. This paper presents a summary of pre-test studies to design the best configuration of DPW to improve the overall resiliency of the structure.