Tuning procedure for the resilient slip-friction joint (RSFJ)

Self-centering friction dampers like the Resilient Slip-Friction Joint (RSFJ) are increasingly relevant for their ability to (1) damp earthquake-induced vibrations without degradation, and (2) prevent residual deformations after earthquakes, thus reducing both damage and downtime. One of their main advantages is a highly customizable load-deformation behaviour, which makes them versatile across various structural applications. Taking advantage of this, however, requires a degree of intuition and iteration to obtain suitable designs. This paper derives an objective and systematic procedure to generate all possible combinations of damper parameters that can produce a custom flag-shaped hysteresis. Equations are obtained to calculate the parameters explicitly and the procedure is validated with existing experimental data. A modelling example is included to demonstrate how the dampers in a three-storey structure can be tuned automatically to provide the global response required. Nonlinear time-history analyses show that the procedure is effective at tuning the dampers simultaneously to achieve the displacement targets and linear deformation profile specified from a displacement-based design.