DEVELOPMENT OF RAILROAD TRACK DEGRADATION MODELS

Maintenance of railroad tracks is both costly and difficult to manage effectively. The track geometry measurement car allied to modern data procesing techniques is a valuable tool that can be used to improve railroad safety and the cost-effectiveness of track maintenance. An approach to using track geometry data in maintenance management being developed under a joint FRA-Consolidated Rail Corporation (Conrail) cooperative program is outlined in this paper. The functional requirements of track are to permit the safe and economic movement of rail traffic. The definition of track quality indices (TQls) derived from track geometry data to reflect the ability of track to meet functional requirements and progress in the development of track deterioration models are described. The models predict how track quality, as measured by TQls, changes as a function of causal parameters, such as traffic, track type, and maintenance. Preliminary track deterioration models have been developed by using a combination of empirical statistical analysis and engineering analysis, and the uses of deterioration models in track maintenance planning are discussed. The statistical analysis is supported by a data base of track quality and causal parameter information for 350 miles of Conrail freight trackage obtained during a 4-year period.