00196648

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http://onlinepubs.trb.org...s/trr/1978/685/685-003.pdf

https://scholar.google.co...idge&publication_year=1978

In the development of roadside safety improvement programs, many types of obstacles have been identified as being hazardous. However, little attention has been given to the hazard of driveway slopes along noncontrolled and limited-access roadways. It was the purpose of this study to assess the hazard posed by such driveway slopes and to determine the cost-effectiveness of flattening them. The degree of hazard was measured in terms of the expected number of injury (fatal or nonfatal) accidents per year resulting from a vehicle traversing the slope. The probability of injury in a run-off-the-road encroachment of a driveway slope, which was used to compute the degree of hazard, was derived from severity indexes computed from results obtained from the highway vehicle object simulation model to simulate a standard-sized automobile traversing driveway slopes under encroachment conditions of 91-km/h (55-mph) speed at 10 deg encroachment angle in a free-wheeling steering mode. The results of this study indicate that (a) driveways are a roadside hazard, (b) the most cost-effective driveway slope design standard is 8:1, and (c) flattening to an 8:1 slope is the most cost-effective driveway slope improvement. The cost-effectiveness methodology used in this study provides a common basis for comparing driveway slope improvements with other types of improvements in the management of roadside safety improvement programs. /Author/

Publication of this paper sponsored by Committee on Geometric Design. Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved.

01414337

pp 14-19

1978

Transportation Research Record

0309028302

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Figures (6) ; Photos; References (15) ; Tables (4)

Cost effectiveness; Driveways; Improvements; Slopes

Design; Highways; Hydraulics and Hydrology

TRIS, TRB

Sep 15 1979 12:00AM

• DETERMINING DESIGN FLOWS FOR CULVERTS AND BRIDGES ON UNGAUGED STREAMS: A WATERSHED RATIONALE. ABRIDGMENT
• EARTH BERMS AND THEIR ACTUAL AND PERCEIVED EFFECTS ON NOISE AND PRIVACY IN ADJACENT NEIGHBORHOODS
• EDGE-OF-PAVEMENT PROFILES
• HYDRAULIC AND SAFETY CHARACTERISTICS OF SELECTED GRATE INLETS. ABRIDGMENT
• PAVEMENT WIDTH STANDARDS FOR RURAL TWO-LANE HIGHWAYS. ABRIDGMENT
• RAINFALL INTENSITY-DURATION-FREQUENCY CURVES DEVELOPED FROM (NOT BY) COMPUTER OUTPUT
• SUPERELEVATION AND CURVATURE OF HORIZONTAL CURVES