Railway Monitoring and the New Leica GeoMoS Railway Template
Authors: Madalina Craciun, Lidija Spiranec, Steve Thurgood, Megan Hansen
With rail transit numbers continually rising, railways need to keep an increasing number of people and freight moving safely and on schedule. However, when ageing infrastructure, geological instability, nearby construction work, or other factors cause movements to any part of the railway – from the tracks to the supporting infrastructure – the impact can be immense.
Consider a 12-carriage train weighing up to 1000 metric tons, travelling 300 km per hour: when encountering even small changes in the track, the train can derail, crash, or breakdown. At worst, this endangers human life and, at best, causes significant delays with high costs to the railway company. The impact spreads to passengers and the businesses who depend on active railways to deliver passengers and freight on time and intact.
Regular monitoring of the railway and supporting structures provides information that engineers, network operators and infrastructure managers use to mitigate these risks and promote safety. Integrated monitoring systems combining high accuracy measurement instruments, communication devices, and sophisticated software facilitate reliable real-time deformation insights.
In this expert insight, Leica Geosystems Product Engineer and railway monitoring expert, Madalina Craciun, provides an overview of railway monitoring and the Leica Geosystems solution, including the new Leica GeoMoS monitoring software feature that streamlines setup and increases configuration accuracy.
Why monitor railways and nearby infrastructure?
Common factors impacting railways
Changes to track geometry and unstable railway infrastructure or earthworks can result from a range of interconnected factors.
Railway earthworks, including embankments and cuttings, keep track gradients to a minimum for efficient travel. However, geological movement, natural hazards, or adjacent construction create risk areas where sudden events are more likely to occur. An unstable slope that collapses and releases vast amounts of soil onto the railway can derail trains, damage the tracks, and harm surrounding infrastructure.
Additionally, construction or excavations near railways can cause movements impacting the structures that facilitate train passage. Tunnels, bridges, retaining walls, masts, or gantries, and the track bed itself can become unstable. For example, if the area surrounding a rail tunnel moves because of excavations at an adjacent road construction site, the track could also be impacted, making the safe passage of trains impossible.
Changes to the original geometric position of the track, including the rail, sleepers, rail fasteners, ballast, or subgrade, pose serious risks to trains as well. Ageing railways and the frequent passage of heavy trains affect track geometry, along with variations to the subsurface, such as changing water levels.
Monitoring: the solution for safety
Regardless of cause, deformations can create conditions that endanger passengers, impair railway operations, and lead to delays that incur costs.
To assist risk mitigation and provide reliable railway infrastructure, monitoring systems deliver complete information about movements, allowing asset owners or operators to make quick and informed decisions to intervene before major events occur. Crucial data provided by monitoring the stability and structural health of the railway enables engineers to take relevant actions.
Railway monitoring methods and technologies
Track geometry and structural stability
Each railway monitoring project’s measurement specifications are unique and determined by the type of railway line, its location, speed, and use. The methods used to measure track geometry and rail infrastructure stability are based on risk level, access, and measurement interval or duration.
Railway tracks, made up of interconnected components, are measured for different aspects like cant, twist, horizontal alignment, gauge, and rail height. This track geometry data ensures the track has not deviated to a condition that would impact safe operation. Similarly, structures and slopes supporting railways are measured for movements.
Track geometry can be measured using traditional techniques, like cant and gauge sticks and railway geometry trains. However, these must be manually operated and require stopping railway traffic to allow safe access for engineering teams. Geodetic monitoring sensors, such as total stations measuring prisms, can be deployed in both campaign or automated monitoring setups depending on the frequency and types of data collection required. When automated, this method has the benefit of providing displacement data while lines are in operation.
Leica Geosystems Total Monitoring for railway
Leica Geosystems total monitoring solutions provide railway projects with best-in-class hardware, software and original accessories, delivering reliable, accurate, and continuous information crucial to safe railway operation.
The Leica TM60, a self-learning total station designed for monitoring, can fulfil the most demanding 3D measurement requirements. The TM60 not only automates measurements, it also automatically learns and recognises targets, enabling faster setup and accurate prism observations even across large areas. Twin cameras allow operators to view and solve site problems remotely and millimetre-level accuracy is supported at long-ranges with fast measurement speeds. Altogether, the TM60 provides the robust data acquisition foundational to effective railway monitoring.
Connected with the Leica ComBox60 for on-site communication management and power, the monitoring system can run 24/7 with no data gaps, providing absolute reliability. For processing and reporting, Leica GeoMoS monitoring software and services enable automated, continuous data collection, calculation, and analysis in real-time.
When combined, this solution keeps surveyor time on the track to a minimum while enabling maximum data acquisition.
Software innovation enabling faster setup: the GeoMoS Railway Template
Streamlined railway monitoring workflows
The newly released version of Leica GeoMoS features a Railway Template that reduces setup time and improves accuracy through centralised configuration.
Railway monitoring requires complex calculations – and accurate configurations form the basis for quality deliverables. Manually entering formulas or exporting data to 3rd software for computations not only creates delays in the initial acquisition and computation of vital data, but also increases the likelihood of mistakes. Unreliable calculations deliver faulty information that can lead to two undesirable scenarios: either failing to inform about relevant movements, or falsely informing about non-existing or non-relevant movements. Both can have severe consequences.
By removing manual configurations and with no need for as-built surveys or design alignment input, the Railway Template allows operators to start monitoring faster and with greater certainty in their calculations. The simplified workflow speeds up setup and improves input accuracy by reducing errors.
Operators can easily configure all required computations to be generated automatically. Then, when total station measurements are acquired, GeoMoS automatically calculates prism coordinates, displacements, and railway parameters like cant, twist, alignments, and others. With the calculated values, GeoMoS generates reports and provides automated notifications if user-defined thresholds are exceeded.
Benefits for all stakeholders
With the Railway Template’s simple configuration, monitoring can start sooner, and providers can confidently deliver reliable results to asset managers.
Additionally, the bigger the project, the bigger the benefits. If, for example, a project has hundreds of points to be measured, configuring rail geometry computations manually could take an entire day. With the GeoMoS Railway Template, configuration is finished in a matter of minutes without any chance for formula input mistakes. This benefit extends to end clients who receive dependable information that enables quick decision making for necessary interventions.
Leica Geosystems solutions have long provided effective, high quality monitoring systems for railways, with sensors and software collecting and calculating complete data. With the new Railway Template in GeoMoS, setups quickly advance to fully configured so vital railway measurements and data analysis can begin and railways can run safely.