Seismic performance of self-centering hybrid coupled wall systems: Preliminary assessments

Hybrid Coupled Wall (HCW) systems consist of reinforced concrete walls connected with steel coupling beams. HCWs benefit from the superior lateral stiffness of the reinforced concrete walls, while the coupling mechanism reduces the moment demand at the base of the walls. The present study investigates the seismic performance of a new HCW system equipped with friction-damped self-centering coupling beams and examines the efficiency of the new system in reducing residual deformations. The coupling beams of the intended HCW system consist of self-centering links, which can be easily repaired after severe earthquake events. The self-centering system utilized in this study features the following advantages distinguish it from conventional self-centering solutions: (i) it eliminates the coupling beams elongation problem (ii) it facilitates the application of pre-fabricated self-centering components to mitigate uncertainties raised by post-tensioning the connections on site. In this paper, the seismic behavior of the proposed lateral load-bearing system is investigated under several ground motion records and intensities. It is demonstrated that the applied self-centering mechanism has the capacity to minimize earthquake-induced residual deformations and repair time without increasing the damage level expected for the concrete walls in conventional HCWs.