Improving Railway Operational Efficiency with Moving Blocks, Train Fleeting, and Alternative Single-Track Configurations

Abstract

With installation of positive train control (PTC) on many U.S. rail corridors, Class I railroads may soon leverage these investments in communications network infrastructure to implement “advanced PTC” systems incorporating moving blocks. Train control with moving blocks can benefit operating strategies that dispatch fleets of multiple trains running at minimum headways. On single-track corridors with passing sidings long enough to hold multiple trains, fleeting may increase the efficiency of train meets, reduce train delay, and yield incremental capacity benefits. Alternative single-track configurations with fleet-length sidings at double the spacing of conventional single-train sidings can facilitate these operating strategies while minimizing additional track infrastructure and associated capital and maintenance costs. To investigate the operational synergies between moving blocks, fleeting, and longer but less frequent sidings, Rail Traffic Controller software is used to simulate and compare the delay performance of train operations on representative rail corridors for different combinations of fleeting strategy, train control system, siding configuration, and freight traffic composition. Operating fleets in conjunction with moving blocks produces the lowest overall train delay in specific cases of low schedule flexibility and heterogeneous traffic. With more efficient meets, moving blocks and/or fleeting primarily benefit low priority trains that typically wait for opposing traffic during train meets. Such incremental line capacity benefits have short-term financial consequences as they allow additional capital investments in double track to be deferred. Knowledge of train delay performance under moving blocks and fleeting will aid railway practitioners evaluating investments in advanced PTC systems and track infrastructure expansion.

Traffic Capacity Assessment of the Selected Track Section on the Slovak Railways Network after the Implementation of ETCS L3 Based on Signaling Principle

“…It is also possible to state that the research mentioned is a continuation of other scientific publications that address the issue of railway infrastructure capacity. In the context of this research, it is necessary to evaluate the capacity occupation and to determine possible infrastructure bottlenecks [42], railway operational efficiency [43], consumption of railway line capacity in the context of different railway signaling systems [44], and estimate railway capacity considering vehicle circulation [45]. It is also necessary to address this issue in the context of modeling and simulation of railway infrastructure [46][47][48].…”

Effects of Hazmat Train Speed Restrictions on Train Delay Performance and Railroad Line Capacity: Comparative Study with Two Railway Simulation Tools

“…Furthermore, since much of the North American rail network contains more than just two train types and single track, future research should examine the effects of these speed restrictions on networks with several train types and on multi-track mainlines, with a sensitivity analysis to compare the importance of these different route factors. Finally, additional train delay and capacity loss mitigation strategies should be investigated, such as fleeting groups of the restricted speed hazmat trains (18,19), or implementing advanced train control systems that incorporate virtual and moving blocks (20), to determine their effectiveness at reducing the impact of hazmat train speed restrictions. International approaches to managing hazmat shipments by rail could also be researched to help inform future policy decisions in relation to hazmat train speed restrictions.…”

Balancing the Service Benefits and Mainline Delay Disbenefits of Operating Shorter Freight Trains

“…Scenarios with moving blocks exhibited consistently lower average train delay than those with fixed block signals. Diaz de Rivera et al ( 50 ) simulated operating intermodal or unit trains in fleets, finding that combining train fleeting and moving blocks can reduce delay relative to cases with just one of the two components present. This study builds on previous research by using simulation methods to investigate the train delay disbenefits of operating more frequent, shorter trains, and the potential mitigation effects of moving blocks and modified track layouts.…”