Development of railway roadbed improvement method for existing lines by reusing deteriorated ballast

Abstract

In the case of ballasted tracks on soil roadbeds, roadbed improvement must be carried out in locations where the ballast has a high mix ratio of fine-particles and the bearing capacity of the roadbeds is insufficient. For this type of roadbed improvement, in most cases the deteriorated ballast is discarded as surplus soil. A new method was therefore developed to make the process quicker and simpler by reusing the deteriorated ballast and mixing it with grout. This study confirms the validity of the method through full-scale model tests. In addition, confirmation was obtained that this method was applicable to existing lines through field tests.