Citation

Bowman BL, McCarthy KP. Transp. Res. Rec. 1986; 1069: 110-117.

Copyright

(Copyright © 1986, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

The results are presented of one task of a study sponsored by FHWA to determine the use and installation criteria of railroad constant warning time (CWT) systems. These systems measure train speed, direction, and distance from the crossing and estimate train arrival time. When a preselected minimum estimated arrival time is reached, the warning displays at the crossing are activated. The result is a more uniform warning time until train arrival for motorists than that provided by traditional train detection systems.

RESULTS of task activities indicate that no quantitative guidelines have been established by either the states or the railroads as to when CWT systems should be installed. Switching activity, annual average daily traffic maximum speed, and train speed variation were found to be variables, however, that were inherently considered when the need for CWT installations was determined. The necessary limits on each of these variables or their combinations that justify installation are apparently judgmental and performed on a crossing-by-crossing basis. Using information from the U.S. Department of Transportation (DOT)/Association of American Railroads (AAR) National Railroad-Highway Crossing Inventory along with the purchasing information supplied by CWT manufacturers, it was estimated that 6,300 crossings already have CWT installations. Discriminant analysis indicated that of all crossings, 19,400 may require CWT systems, which indicates that an additional 13,100 crossings have the physical and operational characteristics that may require CWT systems.

Language: en

Keywords

ROADS AND STREETS - Intersections; ACCIDENT PREVENTION; RAILROAD PLANT AND STRUCTURES