A self-centering moment resisting frame (SC-MRF) is a viable alternative to a conventional MRF for seismic resistant buildings. An SC-MRF is characterized by gap opening and closing at the beam-column interface under earthquake loading. The beams are post-tensioned to columns by high strength post-tensioning (PT) strands oriented horizontally to provide self-centering forces when gap opening occurs. For the SC-MRF investigated in this research, energy dissipation is provided by web friction devices (WFDs) on the beam. The PT strands and WFD each contribute to the moment capacity of the MRF connections. The SC-MRFs in this study are designed to meet several seismic performance objectives. These include no damage under the Design Basis Earthquake (DBE), leading to immediate occupancy performance following the DBE. In addition, under the Maximum Considered Earthquake (MCE) the structure is designed to have minimal damage and achieve the collapse prevention performance. A 7-bay, 4-story SC-MRF prototype building located on stiff soil in the Los Angeles area was designed with WFDs using a performance-based design procedure with the above performance objectives. A 0.6-scale model of two bays of the SC-MRFs was developed and tested at the NEES equipment site located at Lehigh University using the hybrid simulation method to include other parts of the building in the test. This paper presents an overview of the performance-based design procedure, the test results, and an assessment of the design procedure by a comparison of the test results with the expected performance of the SC-MRF.
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