Improved Railway Track Geometry Degradation Modeling for Tamping Cycle Prediction

The railway track geometry condition is a key factor influencing the safety and comfort of train operations, and controlling the tamping cycles of railway tracks. For the scientific disposition of limited maintenance resources, railway infrastructure managers need to predict the tamping cycles based on an accurate grasp of track geometry degradation rules. Taking each 200-m track segment as a research object, the authors analyze the uncertainty and heterogeneity of track geometry degradation based on the discrete evaluation of the track geometry condition. On this basis, an improved track geometry degradation model using Weibull distributions is proposed to accurately estimate the tamping cycle of each track segment. By considering several heterogeneous factors in the model, individualized modeling for different track segments is realized. The developed model was verified by a case study of 100 track segments of the Chinese Lanxin railway line within the jurisdiction of the Lanzhou Railway Bureau. The estimation results of model parameters reflect the influence of various heterogeneity factors on the track geometry deterioration processes and the tamping cycles of track segments. The accuracy of the tamping cycle estimation results indicates that the proposed approach has significance for guiding the management of tamping maintenance of railway track segments. (C) 2018 American Society of Civil Engineers.