PROBABILITY CONSIDERATION WITH A VIEW TO THE ASSESSMENT OF MEASURES INTENDED TO INCREASE THE SAFETY AGAINST DERAILMENT

Different measures are possible for ensuring that safety against derailment is still provided after the introduction of the automatic coupler. To be able to judge the effectiveness of such measures it will be necessary to know the probability of derailment in the event of their application. This report indicates one method for determining the safety against derailment. It is based on the use of statistical data concerning the characteristics of the track profile, the wagon park, the longitudinal forces occurring in trains, the transverse stability of the track, the coefficient of friction, etc. In the case of a horizontal stabilizing articulation, allowance is also made for a deformed coupler arm. Only the effect of the horizontal components of the longitudinal force are considered. Consequently, one of the advantages of the existing side buffers is obviously disregarded. It has been found that the available statistical data is inadequate. To check the possibility of applying the method, estimates are made to complete the missing data. Provided that the estimates are correct the result will be as follows: For existing two-axled wagons, a pin joint or articulation having vertical but no horizontal stabilization will mean an unacceptably high probability of derailment. The likelihood of derailment is reduced, but not sufficiently, if the electropneumatic brake is used. This also applies if a suspension system with limited transverse play is adopted.

• Supplemental Notes:
  • Restrictions on the use of this document are contained in the explanatory material.
• Corporate Authors:

  International Union of Railways

  Office of Research and Experiments
  Utrecht,   Netherlands 
• Authors:
  • Saliger, W
• Publication Date: 1974-4

Media Info

• Features: Appendices; Figures; Tables;
• Pagination: 29 p.

Subject/Index Terms

• TRT Terms: Couplers; Derailments; Prevention; Safety; Statistical analysis
• Old TRIS Terms: Automatic couplers; Question dt34/e
• Subject Areas: Data and Information Technology; Railroads; Safety and Human Factors; Security and Emergencies;

Filing Info

• Accession Number: 00053161
• Record Type: Publication
• Source Agency: International Union of Railways
• Report/Paper Numbers: DT 34/E
• Files: TRIS
• Created Date: Jun 5 1976 12:00AM