Post Processed Reports

All the measured data are also post-processed into various reports presented in table and graphic formats for track geometry, rail profile, overhead contact wire and clearance and ballast profile parameters. Different reports are prepared for use by different levels of management of the railway authority depending on their level of decision making. The following is just an introduction into reports that can be produced since the subject is vast and the specific requirements of a particular railway may differ from another.

3.3.2.1. Track Geometry

The Track Master/Inspector of a specific line needs absolute measurements measured in millimetres (paragraph 3.2.1) at a specific location on the line for carrying out corrective maintenance activities in order of priority (single exceptions report) whereas the maintenance manager requires a summary of the condition of all the line sections under his authority to prioritise workload and scheduling of available resources. The General Manager Maintenance on the other hand needs information for strategic and financial management purposes of the entire railway infrastructure.

As discussed in paragraph 3.2.2 point measurements in millimeters are not of much use to establish general condition assessments as required by higher levels of management for which condition indices

using standard deviations are better suited. Standard deviations are calculated for the following parameters (see also paragraph 3.1):  Average vertical alignment (PRA)

 Average horizontal alignment (ALA)  Twist (TWT)

 Superelevation or cross level (SUP)  Track gauge (GAU)

The TQI is the sum of the standard deviations of the averages of all parameters calculated over a given break length as described in paragraph 3.2.2.

Various reports can now be prepared using the TQI values to compare track sections with one another to establish priorities in terms of the maintenance program and for general investment decision making. Some of these reports are the following:

(i) Track Quality Index Report for 200 m Break Lengths

The TQI 200 Report is provided in a table format (see Figure 28 in paragraph 3.2.2) and can be used to determine where maintenance should be done.

The data can be manipulated by sorting on different parameters to prioritize where the most critical areas exist. Maintenance programme can be drawn up by using cut-off values for the different parameters.

(ii) ADAII Report for 50m Break Lengths

The ADAII calculation derives a travel comfort quality index for selected parameters for pre-selected distances. A 50m break length is used as default. The maintenance quality indexes (ADAII indexes) of the report are based on the horizontal and vertical accelerations the un-sprung vehicle would experience when traveling with maximum allowed track speed over the measured track geometry. This report is often used to give an indication of ballast fouling.

(iii) Curve Report

The curve report is a listing of the following geometry information (refer to Zaayman, 2016, Chapter 8 paragraph 2.2):  The start and end kilometer values of the curve transitions

and circular curve

 The radius calculated from the average offset value  The average cant on the circular curve

 The speed as input for the specific curve  The average gauge on the circular curve

The information on the report reflects the natural characteristics of the curve (i.e. where the train will tend to move the curve to) as opposed to the designed characteristics. By using the report during maintenance tamping, the natural characteristics of the curve is retained.

This report, together with ultrasonic measurements and historical rail break data, is used to plan the grinding program and the rail replacement program on curves.

(iv) Device Report

Any defined ‘devices’ such as curves, turnouts, bridges, tunnels etc. can be chosen between any points and or for any distance and provide the following information:

 The line information similar to other examples above

 The chosen kilometer start and end points with the associated distance

 The TQI value and standard deviation values for all the parameters

 The number of standards exceedences per category  The GPS coordinates of the device

(v) Number of Exceedences per Threshold Report

This report contains the number of exceedences per standards category (‘within the required standard’, ‘deviation from the standard’ and ‘deviation constituting an urgent repair’) per section. See paragraph 4 below on maintenance standards. This report would generally be used to compare the sections within a route with one another.

(vi) Recurrence of Exceedences Report with 50 Metre Break Lengths The recurrence of exceedences report provides the number of exceedences per standards category per 50 metre break lengths that have reappeared over 6 measuring runs which tells maintenance managers that either the maintenance has not been done or, if it has been done, that there is an underlying problem (route cause) which must be resolved first to ensure durability of maintenance activities.

(vii) Accumulative Distribution of Track Quality

Also known as the zone curve or S-curve is derived from the TQI report which is a distribution graph of the TQI values for a section/s (Figure 30). Multiple consecutive measurements can be compared and trends established.

Figure 30: Example of the S-Curve of a Zone Report (Courtesy Plasser South Africa)

The graph shows the percentage of the track section which is smaller than a specific TQI value. This is a valuable tool for management since it indicates the improvement or deterioration of the track, whether the maintenance tactics are effective and if expenditure is sufficient.

The following conclusion can be derived from this chart:

 The closer the chart starts to the y-axis (on the 0% line), the better the best part of the route and vice versa.

 The closer the chart ends to the y-axis (on the 100% line), the better the worst part of the route and vice versa.

 The steeper the gradient of the s-curve, the more uniform the track condition. The ideal situation would be to have the curve as vertical upright as possible which is a track section that will be easier to maintain, since the types of maintenance actions should be very similar over the route. Likewise a very flatly shaped curve means that the overall track condition over the route is very varied. Maintenance on such a section will be more difficult, since the types of maintenance actions that must be performed on this route will be varied.

 The total condition of the route can be related to previous measuring runs by observing horizontal shifts in the s-curve

with regards to previous measurements. A horizontal shift to the right indicates deterioration and vice versa.

 The worst 10% (90%-100% area) normally indicates the condition of track events like turnouts. Monitoring the trends of this area of the chart shows improvement or deterioration of these events.

 The best 10% is never maintained by hand, but kept in check with on-track machines like tampers. If this shows deterioration, the maintenance cycles are too long.

 In areas where temperature changes can influence track quality, this will also be observed in the s-curve. Summer measurements will tend to be further to the right on the chart than winter measurements.

3.3.2.2. Rail Profile Reports

The following electronic data can be provided after post processing for every section measured:

 Rail wear maximums and averages for 20m break lengths  Rail wear maximums and averages for every straight and curve  All recorded rail wear values

 Rail wear maximums and averages for the section as a whole 3.3.2.3. Overhead Contact Wire Reports

The following electronic data is provided per measuring run after post processing for every section measured:

 Quantity of all recorded contact wire defects  Electronic listing of recorded events

 Mast pole report containing contact wire height and stagger at each calculated change in contact wire stagger

 Number of defects per kilometer

 Electronic listing of defects exceeding the ‘deviation constituting an urgent repair’ threshold value

3.3.2.4. Clearance And Ballast Profile Reports

The Tunnel and Clearance System sends one crosscut for every received data break to the Computer Measuring and Analyser System. The system stores the data at the appropriate location in the geometry file. Another software package (called Tunnel Client) evaluates the crosscuts. The report provided is an exceptions report providing the type and size of the exceedence at a specific location.