기존선 고속화 구간 증속시험을 통한 노반 형식별 자갈도상궤도구조 상태 평가에 관한 연구

The conventional railway lines was planed the speed up of over 200 km/h to ensure the competitiveness for a domestic railway. However the general ballasted tracks in a convention line was designed by the minor design class that was set on the design speed of tracks under 150km/m. Therefore, the conventional ballasted tracks was expected to increasing the maintenance cost due to increasing the dynamic track forces by increasing vehicle speed. In this study, the field tests were performed to evaluate that the influence the increasing vehicle speed on the dynamic track responses. Therefore, the prediction equation for dynamic track response was derived, and compared with the different substructure type such as earthwork, bridge and tunnel. The relationship between the track support rigidity, the ballast coefficient and the dynamic track response for various types of substructures currently employed in Korean convention railway line was assessed by performing field tests using actual vehicles running along the service lines. Field tests were performed on ballasted tracks with different substructure type, i.e., earthwork, bridge and tunnel. The experimentally measured track support rigidity and ballast coefficient were compared with the corresponding track support rigidity and ballast coefficient of German railway through field tests for the various substructure types on the service line. We found that the condition of ballast, substructure type and the corresponding track support rigidity and ballast coefficient directly affect the dynamic track response.