Review of Truck Characteristics as Factors in Roadway Design (2003) / Chapter Skim
Currently Skimming:
Pages 166-183
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 166... ...
F-1 APPENDIX F RECOMMENDED CHANGES TO THE AASHTO POLICY ON GEOMETRIC DESIGN OF HIGHWAYS AND STREETS This appendix presents recommended changes in the AASHTO Policy on Geometric Design of Highways and Streets (1) , commonly known as the Green Book, based on the research presented in this report.
|
From page 167... ...
Dimensions for 20 design vehicles representing vehicles within these general classes are given in Exhibit 2-1. In the design of any highway facility, the designer should consider the largest design vehicle likely to use that facility with considerable frequency or a design vehicle with special characteristics appropriate to a particular intersection in determining the design of such critical features as radii at intersections and radii of turning roadways.
|
From page 168... ...
F-3 Metric Dimensions (m) Overall Overhang Design Vehicle Type Symbol Height Width Length Front Rear WB1 WB2 S T WB3 WB4 Typical Kingpin to Center of Rear Axle Passenger Car P 1.3 2.1 5.8 0.9 1.5 3.4 – – – – – – Single Unit Truck SU 3.4-4.1 2.4 9.2 1.2 1.8 6.1 – – – – – – Buses BUS-12 3.7 2.6 12.2 1.8 1.9a 7.3 1.1 – – – – – Inter-city Bus (Motor Coaches)
|
From page 169... ...
F-4 US Customary Dimensions (ft) Overall Overhang Design Vehicle Type Symbol Height Width Length Front Rear WB1 WB2 S T WB3 WB4 Typical Kingpin to Center of Rear Tandem Axle Passenger Car P 4.25 7 19 3 5 11 – – – – – – Single Unit Truck SU 11-13.5 8.0 30 4 6 20 – – – – – – Single Unit Truck (three-axle)
|
From page 170... ...
Recent research has developed several design vehicles larger than those presented here, with overall lengths up to 39.3 m [129.3 ft]
|
From page 171... ...
minimum centerline turning radius (CTR) , the out-to-out track width, the wheelbase, and the path of the inner rear tire.
|
From page 172... ...
radii of the outside and inside wheel paths and the centerline turning radii (CTR) for specific design vehicles are given in Exhibit 2-2.
|
From page 173... ...
represent a composite of vehicles currently in operation. However, the design vehicle dimensions are intended to represent vehicle sizes that are critical to geometric design and thus are larger than nearly all vehicles belonging to their corresponding vehicle classes.
|
From page 174... ...
derive turning path plots, the designer can determine the path characteristics of any selected vehicle if it differs from those shown (1)
|
From page 175... ...
In the text for Widths for Turning Roadways at Intersections on p. 225, in the discussion of design values for Traffic Condition C, delete the reference to the WB-15 [WB-50]
|
From page 176... ...
(such as traffic volume in relation to capacity) to determine where added lanes are warranted.
|
From page 177... ...
2. Speed at entrance to critical length of grade: The average running speed as related to design speed can be used to approximate the speed of vehicles beginning an uphill climb.
|
From page 178... ...
annoying on two-lane roads with volumes near capacity. Lower minimum truck speeds can probably be tolerated on multilane highways rather than on two-lane roads because there is more opportunity for and less difficulty in passing.
|
From page 179... ...
The method of using Exhibit 3-63 to determine critical lengths of grade is demonstrated in the following examples. Assume that a highway is being designed for 100 km/h [60 mph]
|
From page 180... ...
assumed in Exhibit 3-63 may be appropriate as a design control. Second, for the reasons described above, the truck speed at the entrance to the grade may differ from the value of 110 km/h [70 mph]
|
From page 181... ...
Chapter 7 -- Rural and Urban Arterials No changes recommended. Chapter 8 -- Freeways No changes recommended.
|
From page 182... ...
major highway facilities that are designed to accommodate the larger combination units. Such trucks may be present on urban arterials, but seldom turn into or out of local urban streets.
|
From page 183... ...
intersection area to provide positive guidance. This type of pavement marking extension provides a visual cue for lateral positioning of the vehicle as the driver makes a turning maneuver.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.