Abstract
The FE-based coupling method with ballast settlement elastoplastic analysis and track vibration analysis considering unsupported sleepers is developed to accurately evaluate the sleeper-ballast interaction force in deteriorated track. The present method is used to investigate the evolution of the ballast settlement around a junction of concrete slab and ballast layer. In the analysis considering unsupported sleepers, the maximum of the sleeper-ballast interaction force at the sleeper away from the junction increases in progression of the number of loading cycles at higher rate than that without loose sleepers. A larger maximum force causes a larger permanent deformation of ballast layer. This is because the progression of ballast settlement leads to an increase in the number of unsupported sleepers in neighborhood of a supported sleeper.
