"CLOSE HEADWAY" OPERATION FOR BAY AREA RAPID TRANSIT (BART)
The original decision to signal BART for 90-sec headways was based on limited data collected mainly under "dry" and simulated adverse track conditions. Subsequent natural condition testing demonstrated that the corresponding 2.7 mph/sec design brake rate assumption could not be relied on in "wet" or rainy weather; and, consequently, BART has had to operate with station-to-station separation of trains and severe speed reduction penalties. The above restrictions have, at times, caused a well-publicized throughput problem for the transit system. An initial test program was conducted by BART in the winter of 1975, making possible identification of important variables influencing train braking performance. However, firm conclusions regarding safe stopping distances could not be reached based on the 1975 data. In order to solve BART's stopping distance problem and provide "close headway" operation to the public as originally promised, a major full-scale test program was conducted during the winter months of 1977-1978 to accurately determine train braking performance under adhesion-limited conditions. This program made use of some basic concepts from the statistical theory of experimental design. The main results and conclusions of this study, recommending safe and efficient "close headway" operation for BART, is the subject of this paper.
- Contributed by the Rail Transportation Division of ASME/IEEE Railroad Conference, Colorado Springs, Colorado, April 24-25, 1979.
American Society of Mechanical EngineersTwo Park Avenue
New York, NY United States 10016-5990
- Leon, G B
- Brumberger, N A
- Publication Date: 1979-1-31
- Features: Figures; References; Tables;
- Pagination: 12 p.
- TRT Terms: Adhesion; Block signal systems; Braking performance; Instrumentation; Rain; Rapid transit; Speed limits; Tests
- Identifier Terms: San Francisco Bay Area Rapid Transit District
- Old TRIS Terms: Block systems
- Subject Areas: Operations and Traffic Management; Public Transportation;
- Accession Number: 00194645
- Record Type: Publication
- Source Agency: American Society of Mechanical Engineers
- Report/Paper Numbers: 79-RT-6 Conf Paper
- Files: TRIS
- Created Date: Jun 30 1982 12:00AM