Self-centering friction energy dissipation brace with non-prestressed Disc Springs: Concept validation

Self-centering energy dissipation braces (SCBs) provide both recovery and energy dissipation capacities during earthquakes. However, the deformation capacity of conventional SCBs is often constrained by the high-level prestress required in elastic self-centering components, limiting their hysteretic performance under severe earthquakes. To address this issue, this study introduces a novel self-centering brace with non-prestressed disc springs (NP-SCB). The configuration, working mechanism, and theoretical restoring force model of the NP-SCB are presented. In order to validate the concept, finite element analyses were then performed to evaluate the effects of key parameters, including sliding friction force (F_s) and disc spring stiffness (K_d), on its hysteretic performance, self-centering behavior, and energy dissipation capacity. The results revealed that the proposed restoring force model accurately predicted the hysteretic response of NP-SCBs, characterized by distinct “flag-shaped” and “spike-shaped” curves. The energy dissipation capacity was closely associated with the reactivation displacement and can be enhanced by reducing F_s or increasing K_d. The NP-SCB exhibited excellent self-centering performance, with a maximum residual axial strain of only 0.046 %. Compared to traditional pre-stressed SCBs, NP-SCBs showed a 9.86 % to 500 % improvement in deformation capacity. NP-SCB's seismic resilience can be enhanced by optimizing sliding friction force and disc spring stiffness.