Characteristics of stiffness–damping relationships in ballasted tracks for health condition evaluation

Abstract

ABSTRACT The condition of ballasted track critically affects their safety and functionality. Several studies have focused on establishing guidelines for evaluating the condition of ballasted tracks. Light Falling Weight Deflectometer (LFWD) is considered as a quantitatively viable technique for conducting routine maintenance checks in Korea, serving as a potential replacement for impact sound assessment. LFWD measures the impact force applied to the sleeper and the resulting deflection, which provides the apparent stiffness and damping factor of the ballasted track. Finite element analysis (FEA) was adopted to simulate the LFWD tests as the ballasted tracks deteriorated. The FEA results revealed the influence of the deteriorated ballasted tracks on the stiffness-damping relationship. The characteristic curves of the apparent stiffness and damping factor derived from FEA were applied to investigate the condition of 12 ballasted tracks for high-speed trains in Korea. These investigations provided a visual representation of the progressive stages of deterioration in ballasted tracks.