Seismic performance evaluation of a multi-slit damper

This research proposed a new displacement-dependent energy dissipation device for seismic protection of framed structures. The multi-slit damper (MSD) was developed by combining weak and strong steel slit dampers in series. The MSD has two stages of energy dissipation with different yielding forces and stiffnesses: for low to medium earthquakes, the weak-slit damper yields and dissipate seismic energy. For stronger earthquakes, further deformation in the weak slit damper is restrained and the strong-slit damper begins to dissipate the energy. Cyclic loading test of a prototype MSD was carried out to evaluate the seismic energy dissipation capacity. Finite element analysis of the test specimen was also carried out for validation of the test results. A simplified numerical model of the MSD was developed in the framework of commercially available structural analysis software. The seismic performance of a reinforced concrete (RC) model structure retrofitted with the MSD was investigated and was compared with that of the model structure retrofitted with conventional slit dampers. The experimental and analysis results showed that the MSD is effective in reducing seismic response of framed structures.