Identifying system criticality of signals in a complex area

Network Rail commissioned trenolab and Arup to prototype an approach to identify assets that are critical to the delivery of train performance – using Trenissimo to simulate train movements in the vicinity of Woking and Woking Junction.

The project started with the implementation of a function in trenissimo to allow running iteratively a simulation for all combinations of incidents,triggered by user-selected trains at all signals within an area. Such function is unique on the market and thus not available in other tools.

Then, a few test scenarios were run. Results of runs similar to real failures were compared against real data, obtaining an initial validation of the total recovery time and impact on single trains. Based on this positive outcome. all signals in the woking area were tested, considering trigger trains in the AM and PM peak, as well as off-peak; the simulation was repeated considering a duration of the failure of 7.5 and 15 minutes.

While the ranking of system criticality of signals was in line with the expectation, the amount of delays caused by the different signals and the huge difference among signals proved extremely interesting for the client. The positive result of the study led to the further development and release of the new function in trenissimo.