The graphical portrayal of train operations using time-distance diagrams has long been used to develop schedules and for other analyses. The availability, however, of relatively simple, practical, user-friendly computerised tools to do the related calculations and plots is limited. The development and application of a package of PC-driven programs that accurately simulates train operations, plots bi-directional operations charts and schedules, and allows sensitivity testing of various operating parameters are discussed. The package was tested using data derived from the operations of Philadelphia's Market-Frankford subway elevated rail rapid transit line. It then successfully generated graphical schedule (string-chart) diagrams for this two-track line under a series of operating assumptions. Of special interest was the testing of the present schedule while a section of track 599 m (1,964 ft) long between two stations was taken out of service. Such a package can be easily developed and used for a variety of sensitivity analyses, graphical scheduling, and other operational tests.
Abstract