Experimental study of a self-centering prestressed concrete frame subassembly

This paper presents the experimental investigation of the behavior of a 0.5-scale, one-bay, one-story self-centering (SC) moment resisting concrete frame subassembly under cyclic loading. The SC frame utilizes post-tensioned (PT) beam-column connections and column-foundation connections to provide the re-centering capabilities after earthquakes. Beam web friction devices are included in the beam-column connections to provide the adjustable energy dissipation capacity, and steel jackets are used at the beam ends and column bases to avoid concrete crushing at the contact interfaces. The influence of various parameters (i.e. initial PT forces in the beam and columns, friction forces, etc.) on the seismic behavior of the SC frame is experimentally examined, and it is observed that the frame subassembly performed well up to a 2.5% drift with only minor damage in concrete cover of the beam, and the column remained damage free. To avoid the stiffness reduction upon unloading and to achieve desirable energy dissipation, the stiffness of the friction devices and connecting bolts should be properly enhanced in future study.