Concept, analysis, and test of a self-centering viscous damper with displacement capacity enhancement

Resilience of civil engineering structures is getting more and more attention from experts as well as public. Residual deformation has been used as an important index to measure the resilience of structures subjected to earthquakes. A self-centering viscous damper (SCVD) is proposed with prestressed steel strand as recentering element and viscous oil to dissipate energy. A hydraulic mechanism for displacement capacity enhancement is designed to resolve the problem of insufficient deformation capacity of the recentering steel strands. The working principle, numerical modeling, specimen design, and cyclic tests of the SCVD are described in detail. A real-time hybrid test of a structure incorporating the SCVD validates the excellent effect of the SCVD on the seismic residual deformation of the structure.