Abstract: For the sake of strengthening safety management of railway operations, the restriction conditions for maintaining track regularity were studied. Firstly, based on test data of a certain railway collected by track measurer and safety inspection car, track geometric dimensioning and interaction relationship of vehicle and track were analyzed, and factors that affect track irregularity under comprehensive action of related infrastructure deformation, train operation, maintenance and repair were identified. Then combined with actual situation of maintenance and repair, the typical maintenance methods for different track diseases were summarized. Finally, it systematically explained that the track, as a basic part of railway infrastructure and an important part in direct contact with the wheel set of locomotive and vehicle, its regularity played an important role in safe, smooth and fast train operation. The results show that different track irregularities have various effects on the safe and stable operation of locomotive and vehicle, that track irregularity is affected by many factors such as deformation of infrastructure, interaction of vehicle/track and maintaince mode, and that track irregularity can be controlled by scientific and reasonable maintenance and repair.

Key words: track irregularity, safe operation, geometry deviation, maintenance and repair, differential settlement