4. Effective management method for rail corrugation

Rail corrugation can lead to an increase in track side noise emissions, deterioration of track material and track irregularity, and therefore needs proper maintenance. However, identifying corrugated sections in the longitudinal direction of the line in order carry out the appropriate rail grinding is a problem. A device was developed to permit continuous measurement from the track side, and a system was developed to enable effective maintenance management.

First, a trolley type device was developed to permit continuous measurement and detection of rail surface irregularity such as rail corrugation (Fig.1). Developed "rail surface irregularity continuous measurement device" is able not only to measure rail corrugation on the top of rail surface of the low rail but also that on gauge corner of the high rail. Using this device it is now possible to detect both the occurrence conditions and state of progression of rail corrugation (Fig.2).

Following on from this, a "rail corrugation management system" was developed using regular rail surface irregularity measurement data and axle-box acceleration data. (Fig.3). This system offers a more efficient method for managing rail corrugation, since it can be used to estimate which sections of rail require grinding in which order of priority.