2021 Volume 77 Issue 2 Pages I_467-I_476
With the aim of reproducing the resonance phenomenon occurring in actual high speed railway PRC girders, this paper developed an analysis method that combines a nonlinear equivalent reduction model of PRC girders and a dynamic analysis method that utilizes the railway operation information big data. First, a nonlinear equivalent reduction model which takes into account the hysteresis characteristics after concrete cracking was developed. The validity was confirmed by comparing results of the reduction model with the actual measurement and the three-dimensional finite element model. Using this model, the mechanism of the resonance phenomenon was clarified, that stiffness of the PRC member gradually decreases by repeatedly experiencing simultaneous double-track loading when train passing. As a result of evaluating the trends of the dynamic response based on the train operation analysis, the stiffness sharply drops due to double-track loading after the fundamental timetable revision, and the displacement significantly increases since the resonance speed gets close to the operating speed. These simulated results are consistent to the actual observed phenomenon and measured displacement responses.
