橋梁等の地震時挙動

[CS12-63] Modal Identification of Elevated Bridge through Microtremor and Impact Tests using Frequency Domain Decomposition

*ヘイユウ チン¹、飯山 かほり¹、盛川 仁¹、坂井 公俊²、北村 光³ (1. 東京工業大学、2. 鉄道総合技術研究所、3. 鉄道・運輸機構)

Keywords:Frequency Domain Decomposition technique, Modal Identification, Microtremor, Impact test, Continuous span bridge

In this paper a continuous span elevated bridge is analyzed by using Frequency Domain Decomposition (FDD) for microtremor and six impact tests. Difference between applying FDD to microtremor and impact test is proposed. Impact test can excite the closed mode that doesn’t appear in microtremor. What’s more, a single span bridge which is the preliminary constructed part of the continuous span bridge is compared with the continuous span bridge. The lower peak frequencies appear during the construction from single span to continuous span, and changes of modes at the same peak frequency are proposed.