In civil engineering, a reverse curve (or "S" curve) is a section of the horizontal alignment of a highway or rail route in which a curve to the left or right is followed immediately by a curve in the opposite direction.
On highways in the United States reverse curves are often announced by the posting of a W1-4L sign (left–right reverse curve) or a W1-4R sign (right–left reverse curve), as called for in the Manual on Uniform Traffic Control Devices.
On rail routes, reverse curves can cause buffer-locking. On the Northeast Corridor in the United States, these also hinder the development of high-speed rail.
See also
References
Mundrey (2000). Railway Track Engineering. McGraw-Hill Education. pp. 164–179. ISBN 9780074637241. 9780074637241 ↩
Harry Rubey (1956). Route Surveys and Construction. Macmillan Publishers. pp. 86–88. https://books.google.com/books?id=G35kAAAAMAAJ&q=railway+%22reverse+curve%22 ↩
Federal Highway Administration (1971). Manual on uniform traffic control devices for streets and highways. U.S. Government Printing Office. p. 67. /wiki/Federal_Highway_Administration ↩
"Analysis: Long road ahead for improving Northeast Corridor speeds". https://www.trains.com/trn/news-reviews/news-wire/analysis-long-road-ahead-for-improving-northeast-corridor-speeds/ ↩