動吸振器を用いた配管系の地震応答低減効果に関する調査

抄録

There are two types of optimal design for dynamic vibration absorbers: fixed-points theory and minimum variance criterion. The reduction effect of dynamic vibration absorbers designed based on these two design theories on seismic response of piping systems was investigated. Though transfer functions or frequency response curves are usually used to evaluate the performance of dynamic vibration absorbers, the floor response spectrum which is generally used in seismic resistance evaluation was adopted in this study, because it targets non-stational random vibrations such as seismic waves. Using a small-bore piping with a dynamic vibration absorber modeled in a two-degree-of-freedom system, the response reduction effect based on two design theories was evaluated by comparing the floor response spectra for the seismic waves. As a result of the comparison, there was no difference between the reduction effect sizes of the two design theories. Also, these effects of reduction equally worked in addition to the response decreasing by the damping ratio of piping. For seismic waves, it was found that the difference between the response reduction effect of dynamic vibration absorbers based on the two design theories was unlikely to appear.