せん断・ねじり (1)

[V-593] Vibration characteristics evaluation of RC and PRC beam members assuming cyclic train loading in use condition

*徳永 宗正¹、渡辺 勉　¹、池田 学　¹、曽我部 正道¹ (1. 鉄道総合技術研究所)

Keywords:Railway viaduct, resonance, fatigue test, concrete member, effective stiffness, equivalent damping

With the improvement of train operation speed and the spread of low rigidity girder such as PRC girder, remarkable cases of resonance due to the crack progress in concrete members during train passing are reported. The aim of this paper is to evaluate the vibration characteristics of concrete beam members. By static loading test, the effective stiffness of RC member is consistent with the existing formula, while the effective stiffness of PRC member is overestimated and consistent with Branson's law. From the fatigue test, the stiffness decreases about 6-16% for RC members and 10-33% for PRC members, and the equivalent damping decreases to about 4.0% to 0.5% and 1.5% to 0.5%, respectively.