Mechanistic and performance evaluation of a mesh-type elastic pad–ballast system under dynamic loading: Experimental and numerical investigation

The conventional under-ballast mats (UBMs) primarily rely on material properties and lack structural optimization, resulting in limited vibration mitigation performance under complex loading conditions. To address these limitations, this study presents and systematically investigates an innovative honeycomb mesh-type elastic pad (MTEP) designed for vibration mitigate in ballasted track. Firstly, a detailed finite element (FE) model of the MTEP prototype was established to evaluate its internal stress behavior. The structural stability of the MTEP under high loads was further assessed through impact failure test of drop-weight. Subsequently, a large-scale discrete element method (DEM) model of the ballasted track was developed to simulate the nonlinear contact and frictional interaction between ballast particles. The reliability of the DEM model was validated through resistance tests. To further explore the dynamic performance of the track system with MTEP installation, a coupled vehicle-ballasted track dynamic model was constructed. Based on this model, the vibration transmission behavior of the track system was analyzed under various train speeds. Additionally, on-site measurements were carried out to validate the vibration mitigation effectiveness of the MTEP. The results indicate that the distinctive structural configuration of the MTEP improves internal stress distribution and effectively mitigates the vibration level of the track system. Notably, the most significant attenuation occurs at the ground, where a maximum vibration reduction of 12.88 dB is observed. These findings provide theoretical and experimental support for the structural optimization and engineering application of UBMs in railway systems.