Operating management of a large railroad must frequently deal with problems which effect major segments of the railroad or possibly even the entire railway system. These types of problems include train scheduling, routing, major track and signal improvements, as well as changes in operating policies. The Chessie System has developed the Mini-Network Model as a tool for aiding management in evaluating the impact of these types of problems and the effect of proposed solutions on operations. The Mini-Network Model is a computer simulation model which has the ability to duplicate over-the-road train operations on single and multiple track territories. The modifier, Mini, is used because, unlike other network models, simulation is performed at the train rather than the car level. When required for the specific application, yard and terminal functions can also be simulated. On single track territory, the model will arrange meets and passes with due consideration given to train priorities, track occupancy and trackwork configurations. The major application of the model has been in preparing for the federal (USA) 12-hours of service law. Under this rule, train crews cannot exceed 12 hours on continuous duty between call and relieve times, which represents a change from the 14 hours previously permitted. The model was used on certain regions of the Chessie System to project what will happen under the new law if schedules and facilities remain unchanged. The effect of proposed additional main tracks, yard improvements, and schedule changes to relieve the operating difficulties imposed by the constraint on crew service hours were also simulated. The end product was a recommendation for train schedule revisions providing satisfactory operations under the new law. The model has also been used to aid in the scheduling of a new train service over an already busy territory and it is currently proposed to use the model in studying the effects of single tracking of a multiple main track territory.

  • Supplemental Notes:
    • Presented at Fourth International Symposium on Railroad Cybernetics, AAR/UIC/IRCA, 21-26 April 1974, Washington, D.C. This paper was also published in the November-December, 1973 issue of Rail International, which is available from E.S.L.
  • Corporate Authors:

    International Union of Railways

    14 rue Jean Rey
    75015 Paris,   France 
  • Authors:
    • Drucker, R W
    • Jewell, B L
    • Borden, R P
  • Publication Date: 1974-4

Media Info

  • Features: Figures;
  • Pagination: 5 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00053774
  • Record Type: Publication
  • Source Agency: International Union of Railways
  • Report/Paper Numbers: Paper
  • Files: TRIS
  • Created Date: Apr 17 1976 12:00AM