A Mathematical Approach for Recreation Non-symmetric 2D Railway Alignments

The constant passage of trains on the railways tracks causes, in the course of time, geometric deviations that must be corrected periodically by means of a track calibration process. It consists of designing a new horizontal alignment, called recreated alignment, as close as possible to the deformed center track fulfilling also the technical constraints according to the operational requirements of the railway. In recent years different models have been proposed to address this task. This paper proposes, firstly, a new geometrical model for the definition of horizontal alignments to deal with non symmetric transition curves at both sides of a circular curve and secondly, a two-stage optimization algorithm to compute the recreated alignment. The usefulness of this model is tested with two academic examples showing its good behavior. The paper ends with a conclusions section in which a brief description of future work is also presented.