Prediction of high-speed railway vibration signal and its wave field energy characteristics in viaduct site based on simplified source mechanical model

This paper proposes a simplified seismic source mechanics model for predicting high-speed railway vibration signals in viaduct sites and further analyzes the frequency and spatial energy characteristics of the vibration wave field based on numerical simulation. The method effectively reduces the prediction time of the environmental vibration of high-speed railway trains. It aligns more with the actual vibration wave field than the existing seismic source model. First, a simplified seismic source model is established by equating the mobile high-speed railway train as a simplified force source excited by multiple bridge piers with delayed excitation; subsequently, the energy distribution characteristics of the wave field in the site of the viaduct are reflected based on the seismic source model. Finally, the time-domain and frequency-domain characteristics of the simulated high-speed railroad vibration signals are verified by on-site monitoring tests. Overall, this new simplified source model can be effectively applied to the rapid prediction of environmental vibration of high-speed railway trains in a viaduct site, with a small computational workload, and can be effectively used in environmental vibration assessment and other fields, which improves the prediction efficiency under the premise of ensuring the accuracy of the signal characteristics.