Rail assets are organised into large hierarchical asset classes that are interdependent to make up a rail system. These rail assets are organised using detailed, lower-level assets built from taxonomies and ontologies tailored to each jurisdiction within the rail industry. Railway interaction and operation of assets must conform to various stringent rail regulations. Safety has a massive focus.
Taxonomy organises data hierarchically, while ontology
models both hierarchies and complex relationships between entities and their
properties. In the rail industry, ontologies are crucial for successfully
modelling assets.
The picture shows examples of significant assets (high-level)
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| Main Railway Infrastructure Assets high-level overview. |
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| An AI-generated image to explain commonly used railway terms. |
The railways consist of "rolling stock, rail infrastructure, and environment"; these components have multiple relationships with one another.
1. Rolling stock is the trains.
2. Rail Infrastructure relates to:
2.1. Electrification/power/energy, generally used for power supply for signalling, train power, and telecoms. Key protocols for using devices are MQTT, MODBUS and IEC
- UK network supplies at 400kV, and train propulsion uses 25kV (AC) for Mainlines and 1-3kV (DC) for requiring step-down. Train propulsion power is referred to as Traction Power Supply.
- Non-Traction Power Supply, used for signalling, station power, and lighting
- Overhead Line Equipment (OLE) is critical in railway electrification. OLE span - Longer spans reduce the number of masts, lowering installation costs—but only if mechanical and electrical limits are respected.
- Overhead Contact System (OCS) or Third Rail: Transfers power to trains.
2.2. Telecommunication, track-to-control, and train-to-control are used to communicate, including sensors and IoT devices.
2.3. Signalling relates to ensuring train safety so the train knows there is a train ahead of it, and issues when to slow down.
2.4. Track Engineering, also known as Rail Engineering and The Permanent Way, involves the rails, connectivity, support, extensive physics and geometry, steel rail installation and joining, ballast (the ground on which the track is laid), drainage, substructure, and sleepers. It gets detailed with rail joins (Fishplated) and even the welding process used. Fastening types, baseplates, sleepers, off-track maintenance such as hedge trimming (you won't believe the rules unless you work in the rail industry) ...
SCADA systems integrate sensors, Remote Terminal Units (RTUs), Programmable Logic Controllers (PLCs), and Human-Machine Interfaces (HMIs) to collect real-time data, automate processes, and ensure operational safety and efficiency. In rail, SCADA typically manages traction power, station systems, and communications infrastructure
3. The environment refers to the existing conditions before the railway, including the topography and type of terrain, bridges, and rivers.
The interdependencies with the rail industry are perfect for numerous AI scenarios. With all AI, you need high-quality data, and it must be secured appropriately. Bring information from across business functions together to enable automation, ML, and AI, and support better decision-making.
Each country or jurisdiction has different rules for trains, and operators must comply with Health, Safety, and Environment (HSE) regulations. There are industry rules adapted to each jurisdiction and standards that vary between regions. For example, most jurisdictions have a gauge width requirement; in the UK, the standard gauge is 4 feet 8 1/2 inches (1435mm). There are exceptions, such as heritage railways in the UK. There are manufacturing standards for everything. EN13674 is the British Rail specification for the actual pure steel used to manufacture the track to be installed.
ISO 55000/1/2 addresses Physical Asset Management. Building Information Modelling (BIM) enhances the design and construction process, and both apply to Rail Infrastructure. There is generally a disconnect between Asset Management and BIM, and the International Foundation Modelling (IFC) aims to help establish a standardised set of assets for the railway business; we are on v4.3.
SIL4 - Used for critical safety systems such as railway interlocking control systems. Safety Integrity Level is defined in functional safety standards, such as IEC 61508. SIL1 is the lowest level, and SIL4 is where a system has the lowest likelihood of dangerous failure and the best reliability.
References used:
Permanent Way Institution (2023) Understanding Track Engineering. London: The PWI. Available at: https://www.thepwi.org/product/understanding-track-engineering/ (Accessed: 4 July 2025)
Camarazo, D., Roxin, A. and Lalou, M. (2024) Railway systems’ ontologies: A literature review and an alignment proposal. 26th International Conference on Information Integration and Web Intelligence (iiWAS2024), Bratislava, Slovakia, December 2024. Available at: https://ube.hal.science/hal-04797679/document (Accessed: 4 July 2025).
Network Rail (2021) Asset Management: Weather Resilience and Climate Change Adaptation Plan. London: Network Rail. Available at: https://www.networkrail.co.uk/wp-content/uploads/2021/11/Asset-Management-WRCCA-Plan.pdf (Accessed: 4 July 2025).
