Optimizing maintenance of vertical curves in high-speed railways

The relationship between railway alignment and passenger comfort under high-speed driving conditions is even closer, requiring alignment smoothness to a greater extent. However, vertical curve dynamic detection alarm is a chronic, difficult-to-resolve issue in operational high-speed railways. Therefore, a novel method combining alignment parameters and track geometry from the perspective of smoothness is proposed to optimize the curve radius by controlling elevation differences and to calculate track adjustments by improving the long wavelength irregularity. To validate the performance, the proposed method is adopted to develop vertical curve maintenance schemes for Beijing-Hong Kong high-speed railway, and the daily average number of level II warnings of vertical acceleration decreased by 95% after applying the schemes. The results demonstrate that the proposed method effectively improves alignment smoothness in the dynamic detection alarm section. The method still needs to be subsequently extended to improve its adaptability to different irregularity bands and complex line conditions.