Seismic Response Analysis of Industrial Building With Viscous-Friction Hybrid Damper

In great east Japan earthquake, resonances of structures which have long natural period by long period seismic wave were reported. The duration time of the long period seismic wave was more than a few minutes. Meanwhile many dampers have been proposed and applied to actual structures in order to suppress seismic response. However large stroke and energy absorption capacity are required for these conventional oil dampers against the long period seismic wave. In this paper, authors propose a viscous-friction hybrid damper as an effective vibration control device suitable for structures which have long natural period. In general, structures with long natural period resonate with long period ground motion. The hybrid damper consists of an oil damper and a friction damper in series. In our hybrid damper, the friction damper can absorb vibration energy as well, in the case of long period seismic wave. Thus energy absorption of oil damper is suppressed, and the damper retains good performance. In addition, the oil damper of the hybrid damper is effective for small earthquake. In this paper, a boiler building was selected as an example of industrial buildings. The boiler building was modeled as 2-degree-of-freedom for analysis. Seismic response analysis of the building with the hybrid damper was carried out. As a result good vibration control performance was confirmed.