A Novel Optimization Algorithm of Track Fine Adjustment for High-speed Railways

Track fine adjustment of the rails can control the regularity of ballastless track of passenger lines, which is essential for ensuring the high track regularity. Using the three-dimensional coordinates measured by track surveying trolleys, the analogue adjustment of fasteners can be achieved by a piece of special software. However, the method used in the software for analogue adjustment is manually operated. In order to make the track regularity of the reference rail fit the requirements, the low degree of automation of track analogue adjustment needs repeated manual adjustment. The gauge, change rate of the gauge, cant, and twist cannot control lateral and vertical profiles of non-reference rails. Therefore, this paper proposes a novel adjustment algorithm called optimization algorithm of double track fine adjustment (OADTFA), based on L₁ norm optimal principle. In OADTFA, the deviations of endpoints of reference chords participate as constraints for the lateral and vertical profiles, which control not only irregularities of the reference rail but also irregularities of non-referencerails. The strategy of choosing reference chord (e.g. 300 m) for sectional optimization adjustment is point by point. The optimally adjusted value of each fastener can be calculated by simplex method. An analogue adjustment experiment shows that OADTFA can automatically complete analogue adjustment, ensuring the high regularity of double rails anywhere, and give the optimally adjusted values of double rails.