Special edition paper

Track that supports railway cars is exposed to repeated train running load, advancing deterioration of tracks. Thus, it is important to correctly identify the status of deterioration by inspections and to carry out repairs at an appropriate timing. At JR East, we measure dynamic displacement (track irregularity when train load applied) by electric and track inspection cars (East-i) every three months. Material deterioration is periodically inspected by track patrolling on foot and mechanically by inspection devices. With track irregularity for example, when track irregularity exceeds the specified threshold (standard for repair), we estimate the timing for repair based on past experience and car body vibration inspection data to conduct systematic repair. But, even at locations where measurement results have not reached such a threshold, track irregularity may rapidly progress due to factors such as condition of the ballas