Short soil–binder columns in railway track reinforcement: three–dimensional numerical studies considering the train–track interaction

The authors present a numerical study on railway track subgrade reinforcement using short soil-binder columns through injection, below the ballast layer. A 3D FEM program developed in MATLAB that considers the dynamic train–track interaction and the non-linear elastic behaviour of the ballast is used to study the response of the train–track–substructure system and assess stresses in the subgrade. Results suggest that reinforcements have limited impact on the train–track interaction and reduce deviatoric stresses between columns, at the top of the foundation. This method may be particularly relevant in the rehabilitation of old single railway tracks.