Resilient performance of self-centering hybrid rocking walls with curved interface under pseudo-static loading

Frame and rocking wall (FRW) structures have excellent resilient performance during earthquakes. However, the concrete at interfacial corners of rocking walls (RWs) is easily crushed due to local extreme compression during the rocking process. An innovative RW with a curved interface is proposed to prevent interfacial corners from producing local damage, enhancing its earthquake resilient performance (ERP). The precast wall panel with a curved interface is assembled into an integral self-centering hybrid rocking wall (SCRW) by two post-tensioned unbonded prestressed tendons. Moreover, two ordinary energy dissipation steel rebars and two shear reinforcements are arranged to increase the energy dissipation capacity and lateral resistance. Two SCRW specimens and one monolithic reinforced concrete (RC) shear wall (SW) were tested under pseudo-static loading to compare the ERPs of the proposed SCRW and the SW, focusing on studying the effect of the curved interface on the SCRW. The key resilient performance of rocking effects, failure modes, and hysteretic properties of the SCRW were explored. The results show that nonlinear deformations of the SCRW are concentrated along the interface between the SCRW and the foundation, avoiding damage within the SCRW. The restoring force provided by the prestressed tendons can effectively realize self-centering capacity with small residual deformation, and the resilient performance of the SCRW is better than that of monolithic SW. In addition, the curved interface of the SCRW makes the rocking center change and move inward, partially relieving the stress concentration and crush of concrete. The rocking range of the rocking center is about 41.4% of the width of the SCRW.