Cyclic behavior of seesaw energy dissipation system with steel slit dampers

This paper presents an investigation into the cyclic behavior of a passive vibration control system in which steel slit dampers are applied to a seesaw energy dissipation system. The fundamental concept of the seesaw system is the quasi-linear motion mechanism, which enables the bracing members to remain in tension during vibration. The lateral stiffness and strength formulae of the frame with this system are derived first. Six cyclic loading tests were conducted to reveal that the proposed system has a stable hysteretic property and a large energy dissipation capacity. For all specimens, the slit dampers yielded at early stages of the tests around a story rotation angle of 0.001 rad. This property is preferred for energy dissipation properties to reduce story drift in building structures under seismic loads. The important seesaw system characteristic of the bracing members remaining tensile was also observed. The tri-linear hysteretic model is introduced to model the cyclic behavior of the proposed damping system. A comparison of the hysteretic loops and the energy dissipation amount between the model and test results reveals the adaptability of the tri-linear model to the hysteretic behavior of the proposed system. The validity of the stiffness and strength prediction is also shown from the test results.