ABSTRACT
A steel self-centering moment resisting frame (SCMRF) is an innovative structural system for earthquake-resistant design that has the potential to reduce or eliminate structural damage and return to its original vertical position (i.e. self-center) following a major earthquake. Ricles et al. (2001), Garlock et al. (2005, 2007, 2008), Rojas et al. (2005), Chou et al. (2006), Jhuang et al. (2006) and Christopolous et al. (2002) have developed such a system for steel moment resisting frames. The details of these systems vary, but they all have the following in common: (1) the beams in the frames are post-tensioned (PT) by either high strength steel strands or steel bars, which provides a restoring force to the system that results in self-centering (see Fig. 1(a)); (2) energy dissipation is provided by supplemental elements such as top-and-seat angles, steel bars, steel plates, or friction devices; and (3) the beamto-column (or beam-to-wall) connections are characterized by horizontal gap opening (Δgap) and closing under earthquake loading as shown in Fig. 1(b).
