2021年日本福岛地震中桥梁的震害及原因

Bridge damage investigation post 2021 Fukushima earthquake

时隔10年,福岛宫城县海域再次发生大地震。虽然该次地震最大烈度到达6强,但是地震之后实际震害信息较少。作者实地考察了相马跨线桥、相马东大桥和白石藏王新干线桥三处桥梁在该次地震中的震害,并简要分析了其原因。另外比较KiK-net山元(MYGH10)的地表和地下强震仪的波形和频谱成分,指出这一记录PGA较大的原因。通过比较10年前东日本大地震和该次地震中K-NET郡山(FKS018)的记录,讨论了该次地震震害普遍比预期要低的原因。最后,使用多阻尼反应谱分析了该次地震对结构破坏力较小的原因。

After ten years apart from the Great Tohoku Earthquake 2011,the Fukushima Miyagi area were attacked by large earthquake again.Though,the maximum intensity of this earthquake was 6+,but the actual earthquake damage was not cleared yet.In this study,survey was conducted to the stroked area.Three bridges,Soma overpass,East Soma Bridge,Shiroishizao Shinkansen bridge,were reported about their earthquake damage and the mechanism.By comparing the record wave form and Fourie Spectrum of the ground and underground seismometers in KIK-net Yamamoto station,the reason of the large intensity is analyzed.Compared to record of the Great East Japan Earthquake in 10 years agon,and the record of this earthquake in Koriyama station,some discussion was conducted about the reason of less damaged structures.And finally,a multiple damping response spectrum are used to access the impact of this earthquake to structures.