Abstract：According to the seismic problem that beam-column joints of reinforced concrete (RC)
frame may be severely damaged in earthquakes, a new strategy of using sector lead viscoelastic
dampers (SLVD) to retrofit RC frame structures was proposed. Two retrofitting approaches using
encased box-type steel plates and U-shaped steel plates to combine with SLVD were presented. To
study their seismic performance, three RC frame specimens, including one untreated frame and two
retrofitted frame with SLVD (i.e. using above two different connections), were designed and
fabricated. Furthermore, these three specimens were tested under the low-cycle repeated loading
for the hysteretic behavior, bearing capacity, stiffness degradation, and energy dissipation
capacity, etc. The experimental results show that: (a) the frames retrofitted with SLVD have full
hysteretic curves and good energy dissipation capacity, indicating the good retrofitting
performance of SLVD; (b) SLVD may provide certain additional lateral stiffness for the retrofitted
frame, so that the horizontal bearing capacity of frame can be enhanced, and the energy
dissipation capacity of frame can be strengthened due to the delay of occurrence of plastic
hinges; (c) both the encased U-shaped steel plates and box-type steel plates are effective for the
connections between SLVD and major structure, but the two different connections may have slight
effects on seismic performance of retrofitted frames.
