Influence of Signalling Systems on the Capacity of Railways by Lines and Nodes Assessment Methods

In the complex railway networks characterized by mixed traffic, a key focus is the increase of railway capacity by high performances signalling systems, including ETCS/ERTMS and beyond. Nevertheless, the estimation of effects on headway of the introduction of innovations in signalling systems is complex and not consolidated for complex networks characterized by mixed passenger-freight traffic. This study highlights several challenges on line-node capacity calculation of congested network considering a combined effect of routes conflicts in stations on lines and propagation in station of delays suffered along the lines. The paper describes some results of the ongoing research based on the integrated use of analytical methods and simulation to networks controlled by different standard signaling systems and innovative hybrid solutions able to increase the capacity under specific operational conditions. The paper introduces the application of the methods to the complex mixed-traffic network in Trieste railway node, situated in Northeast of Italy, including the main passengers and freight terminals and the lines operated for both services. The objective is to identify the most appropriate technological solutions and methodological approach for the optimization of the network capacity and minimization of the delays.