OPTIMUM CHORD LENGTH FOR CRITICAL SPEED ANALYSIS
Every field measurement is imprecise and inaccurate to some degree, and therefore has associated uncertainty. The critical speed formula has been used for many years to estimate the speed of a vehicle that slips sideways and leaves yaw marks as it traverses a curved path. The inputs required for the formula are the radius of curvature of the path traversed by the vehicle's center of gravity and maximum lateral acceleration the vehicle can achieve before leaving yaw marks. The radius of curvature of the vehicle center of gravity path is generally determined by making an adjustment to the radius of curvature of a yaw mark deposited by the vehicle. This article looks at the consequences of uncertainty associated with measurements taken to determine the radius of curvature of critical speed yaw marks. The focus is on the sensitivity of the critical speed formula to uncertainty associated with field estimates of the radius. Recommendations are given regarding an optimum chord length for making radius measurements in the field.
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Availability:
- Find a library where document is available. Order URL: http://worldcat.org/issn/10826521
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Corporate Authors:
N/A
3004 Charleton Court
Waldorf, MD United States 20602-2527 -
Authors:
- Rose, N A
- Hughes, C M
- Publication Date: 2002
Language
- English
Media Info
- Features: Figures; References; Tables;
- Pagination: p. 18-20
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Serial:
- Accident Investigation Quarterly
- Issue Number: 31
- Publisher: Accident Reconstruction Journal
- ISSN: 1082-6521
Subject/Index Terms
- TRT Terms: Field tests; Highway curves; Speed control; Traffic engineering; Traffic relationships; Traffic speed; Uncertainty; Yaw
- Uncontrolled Terms: Critical speed analysis
- Subject Areas: Highways; Operations and Traffic Management; I73: Traffic Control;
Filing Info
- Accession Number: 00961691
- Record Type: Publication
- Files: TRIS
- Created Date: Aug 15 2003 12:00AM