Behaviors Comparisons and Prediction of Pre-Pressed Spring Self-Centering Energy Dissipation Braces

The pre-pressed spring self-centering energy dissipation (PS-SCED) brace that combines the friction energy dissipation mechanism with a self-centering member comprising combination disc springs is developed and experimentally studied. The configuration of the proposed bracing system is presented and a Bouc-Wen model-based restoring force model is proposed to predict its hysteretic behavior. Two large scale PS-SCED braces with different length and different types of disc springs are designed, fabricated, and tested under low cyclic reversed loadings, and results demonstrate that the PS-SCED brace exhibits stable and repeatable self-centering hysteretic responses with effective energy dissipation capacity. The ductility of the proposed bracing system can be enhanced by employing the disc springs with bearing surface, and increasing the length of the tube members or segments of the disc springs. The symmetry of the bearing force in tension and in compression meets the design requirement for bracing elements. And the proposed restoring force model can accurately portray the hysteretic behavior of the PS-SCED bracing system.