Analysis of Seismic Performance of Self-Centering Concrete Frame Structures Characterized by Low Prestressing and Slope Friction

Due to the difficulty in meeting major earthquake demands with the stiffness and energy dissipation capabilities of traditional self-centering prestressed concrete (SCPC) frames, the inter-story drift of the structure becomes excessively large during seismic events. Additionally, to achieve full re-centering of the structure, high tensioning of steel strands is required, which further reduces the energy dissipation ratio (<italic>β</italic>) of the structure. A self-centering prestressed concrete frame with low prestressing and slope friction (SF-SCPC) was proposed, low prestressing and a high energy dissipation ratio <italic>β</italic> were incorporated into the self-centering prestressed concrete frame, allowing for some residual displacement in the structure to achieve high energy dissipation under large earthquakes. Using a reinforced concrete structure in an 8-degree seismic fortification area as a prototype, semi-self-centering prestressed concrete frames with low prestressing and slope friction (SF-PSCPC), semi-self-centering prestressed concrete (PF-PSCPC) frames with planar friction energy dissipating, and fully self-centering prestressed concrete frames with slope friction energy dissipating (SF-CSCPC) were designed. Nonlinear dynamic time-history analysis was conducted on the structures under design intensity, rarely occurred, and extremely rarely occurred earthquakes to study the impact of energy dissipator forms and initial prestressing parameters on the seismic performance indicators such as inter-story drift, residual inter-story drift, and beam-column damage. The results indicated that effectively combining the slope friction energy dissipation mechanism and low prestressing re-centering mechanism in self-centering prestressed concrete frames could significantly reduce the inter-story drift and decrease damage to main components. The hysteresis curve area of connections in the SF-PSCPC frame is significantly larger than that of the PF-PSCPC and SF-CSCPC frames, indicating higher energy dissipation capacity. Although the SF-PSCPC structure exhibited some residual displacement under rarely occurred earthquakes, it remained within the economically repairable limit of the structure.