Dynamic Stabilizing in Ballasted Railway Maintenance: Novel Model and Parameter Optimization Based on DEM‐MFBD Coupling Method

ABSTRACT Dynamic stabilization is a critical process for enhancing the service performance of the ballast bed. This improvement occurs specifically following tamping activities have been completed. To deepen our understanding of the operational mechanisms of dynamic stabilizing machines and to improve maintenance efficiency, this paper innovatively introduces the block assembly method and polyhedral units for the rapid construction of a 3‐D simulation model of the ballasted track post long‐section tamping. This method enables the high‐fidelity virtual reconstruction of the complete ballasted track tamping process. By considering the spatial coupling vibration effects between the stabilizing machine and the long track panel, we propose a flexible rail transition grid simulation method alongside an eight‐wheel non‐coplanar demodulation technique, culminating in the development of a virtual unit module. Utilizing multimedia coupling theory and equivalent replacement concepts, we establish a high‐fidelity coupling model of dual dynamic stabilizing machines and the ballasted track, with the model validated by extensive in‐situ testing. The findings indicate a non‐positive correlation between the effectiveness of the stabilizing operation and the excitation frequency. Specifically, a high stabilizing frequency does not optimize the ballast bed state, and frequencies exceeding 30 Hz pose a risk of collapse for the side slope ballast. Conversely, when the stabilizing frequency is maintained between 25 Hz and 30 Hz, the change plastic deformation rate of ballast bed is low, and the lowest is 18.5%, suggesting optimal elasticity and effective stabilizing operations. This research provides critical theoretical support for the simulation analysis and operational parameter selection in stabilizing operations.