第五部門：応用数理問題―計算機科学から社会科学まで

[24007-12-05] Frequency Identification Method that can Separate Amplitude-dependent Stiffness Reduction and VBI effect(Proceedings of Symposium on Applied Mechanics)

*Naohiro Ida¹, Kodai Matsuoka², Kiyoyuki Kaito¹ (1. Osaka University, 2. Railway Technical Research Institute)

Keywords:Natural frequency, PRC girder, Crack breathing, VBI effect

Bayesian TV-ARX method has been proposed for estimating the time-varying natural frequencies of PRC high-speed railway bridges from the displacement during train passages. However, existing method cannot separate the bridge frequency reduction effects caused by the crack breathing and vehicle-bridge interaction. To overcome this, a new model was folmulated that introduced the AR coefficient temporal function consisute of the amplitude- and VBI-dependent terms. As a result of numerical validation, the instanteneous frequency reduction could be estimated and the two effects can be separated by the posterior distribution of each term.