00799065

Component

https://doi.org/10.3141/1701-13

http://scholar.google.com...ueza&publication_year=2000

Mathematical models were developed to estimate vehicular speed on curves and tangents in mountain roads. The 85th percentile speed for curves was estimated by using the radius of the curve under consideration, the radius of the previous curve, sight distance in the curve, and tangent length before the curve. The average speed was calculated by using the radius of the curve under consideration, the radius of the previous curve, and sight distance. The 85th percentile and the average speed were estimated by using the radius of the previous curve and tangent length. Speeds adopted by drivers respond not to engineer's design speed but to geometric characteristics of the road. A design procedure is proposed that takes advantage of available design speed and driver behavior on the road at the same time. On a curve, drivers consider two efficiency measures: speed and comfort. On some curves, they prefer to feel a certain degree of discomfort in exchange for obtaining greater speeds. For some geometric conditions, drivers adopt a speed that sacrifices not only comfort but also safety.

This paper appears in Transportation Research Record No. 1701, Design Speed, Operating Speed, and Sight Distance Issues.

English

p. 104-110

2000

Transportation Research Record

0309066808

Figures (4) ; References (6) ; Tables (3)

85th percentile speed; Average travel speed; Behavior; Comfort; Design speed; Drivers; Estimating; Geometric design; Highway curves; Mathematical models; Mountain roads; Safety; Speed; Tangents

Design; Highways; Planning and Forecasting; Safety and Human Factors; I21: Planning of Transport Infrastructure; I82: Accidents and Transport Infrastructure

TRIS, TRB, ATRI

Sep 29 2000 12:00AM

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• EVALUATION OF THE PASSING PROCESS ON TWO-LANE RURAL HIGHWAYS
• GEOMETRIC DESIGN OF LOW-SPEED URBAN STREETS
• NEW STOPPING SIGHT DISTANCE MODEL FOR USE IN HIGHWAY GEOMETRIC DESIGN
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• SAFETY EFFECTS OF LIMITED STOPPING SIGHT DISTANCE ON CREST VERTICAL CURVES
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