Towards a safer and more robust European railway sector
As part of the Shift2Rail programme, “the PLASA project aimed to enhance the European rail sector by improving planning activities of various stakeholders through precise railway simulation and by providing a methodology based on risk assessment to manage its safety,” explains Ying Löschel from Deutsche Bahn AG and project coordinator. Smart planning is key In Europe, different planning tools are used to simulate railway operations. This leads to non-harmonised results with a data landscape lacking proper data interfaces between countries. There is also no implemented tool that can simulate with a high degree of detail or be used for large networks. PLASA set out to address this by gathering knowledge on smart planning approaches, activities, and existing analyses on disruptions and interdependencies in the European railway networks. Through their work, PLASA developed a macroscopic approach to reduce execution time by restricting the level of detail to high-level relations between significant events. Löschel points out: “This approach enables us to simulate a complete day of operation on the entire German network, with around 40 000 trains, under a minute of computation time.” The tested approach seems to allow for accurate results on delays. There is room for improvements in accuracy, but the new approach appears promising and will be assessed further in another Shift2Rail project, PLASA 2. Investigating safety Defining a possible improved management process on the safety of the railway system using a risk assessment was a PLASA priority. This would “support managers who make critical safety decisions in day-to-day operations and in the design phase,” stresses Löschel. Project work also looked at the functionalities of the system and human behaviour to better represent real-life scenarios. PLASA developed a decision model that was applied to three use cases. The results were promising and demonstrated the relevance and added value of the approach. They also showed how it can be applied to a wide range of railway applications. Overcoming hurdles Löschel highlights: “There were difficulties in gathering safety input data and statistics, as railway operators consider this information to be confidential.” She further notes that “the common safety indicators collected by the European Union Agency for Railways are interesting and useful, but they are not detailed enough.” To overcome this issue, some hypotheses have been assumed to compensate for the lack of data. They do not, however, call into question the principle of the approach. Therefore, they should be reexamined and challenged at a later stage to ensure the results produced for the use cases are reliable. Moving forward The work carried out in PLASA will be continued in PLASA 2. The project will extend the simulation tool developed in the PLASA project to handle a wider range of scenarios. The next stage aims to combine the advantages of assessing possibilities for merging the PLASA macroscopic modelling approach with a classical microscopic railway simulation. It will also outline the requirements for a smart planning tool that could be utilised to aid decision-making in intraday planning. The French national railways will also continue the safety work of PLASA. A decision-support tool implementing the model developed within the project will be designed for one of the use cases and the quantification of human reliability will be further investigated.
Keywords
PLASA, safety, European rail, risk assessment, smart planning, Shift2Rail