Ballast failures restored and detecting methodology for lateral resistance of ballast bed during dynamic stabilization

Stabilization can effectively restore the bearing capacity and lateral deformation resistance of the failed ballast bed. However, unreasonable operating modes can also affect the lateral stability of the ballast bed and the status of the line. To improve the quality of stabilizing operations and save the construction cost of new railways, the paper established a stabilizing machine-ballasted track model based on the DEM-MFBD algorithm, and carefully analyzed the contact separation, reorganization and migration characteristics of ballast particles during the stabilizing. The microscopic movement mechanism of ballast particles is revealed. Based on the mapping relationship between the PSD of the lateral vibration characteristics of the stabilizing machine and the ballast bed resistance, a new method for detecting the lateral resistance of the ballast is proposed. This detection method realizes the rapid acquisition and data transmission of the ballast bed status, and uses a stabilizing machine as the force source, without the need to add a reaction force device. Therefore, it is more efficient than traditional detection methods. Finally, a multi-point track panel lateral resistance index is proposed, the stabilizing operation effect is evaluated, and the optimal operation mode is given. The results show that the effects of the front and rear stabilizers on the ballast bed should be considered during on-site stabilization, and the operating frequency of the first stabilizer should be appropriately reduced to increase the number of contacts between ballast particles and improve the stability of the ballast bed after the stabilization. The new method for detecting the lateral resistance of the ballast bed can be used to easily obtain the mechanical state of the ballast bed before and after stabilizing operation under different line conditions. More stabilization times does not necessarily mean better results. This study provides effective guidance for improving the performance ballast bed and adjusting the alignment of ballasted track on newly built railways.