Section 2 - Roadway Flashcards
ADT
Average Daily Traffic = total annual vol/365 days. Indicates general traffic volumes, but should not determine operating loads (Peak Hourly Volume is preferred but not all-inclusive)
DHV
Design Hourly Volume - approx. 15% more than ADT + represents vol. of traffic that is tolerable to avg driver
volume that each road can carry
DHV = AADT(k)(D)
k = percentage
D = direction
Avg Dims/Passenger Car, Standard
16’-8” L x 6’ w x 4’-6” h
Turning Radius = 24’
Avg dims/Passenger Car, Compact
14’-9” L x 5’-8” w x 4’-5” h
Turning Radius = 20’
Avg dims, Intercity Bus
45’-0” L x 9’ w x 14’-0” h
Turning Radius = 55’
Avg dims/City Bus
40’-0” l x 8’-6” w x 8’-6” h
Turning Radius = 50’
Avg dims/School Bus
39’-6” L x 8’ w x 8’-6” h
Turning Radius = 45’
Avg dims/Fire Truck
32’ L x 8’ w x 9’-8” h
Turning Radius = 50’
Avg dims/Trash Truck
28’-2” L x 8’ w x 11’ h
Turning Radius = 35’
Avg dims/Straight body Truck
17’-35’ L x 8’ w x 13’-6” h
Turning Radius = 45’
Avg dims/Conventional Semitrailer
55’-0” l x 8’ w x 13’-6” h
Turning Radius = 50’
Number of basic types of roadways
1 - Primary (Interstate)
2 - Secondary (Other Arterials)
3 - Tertiary(Collectors)
4 -Local
Freeway
The most rapid and largest volume through-traffic system across and between urban areas. Best characterized by its limited access and grade separated intersections. This includes
expressways and parkways. (typ. ROW = 120’+, 4+ lanes @12’ w)
Major Arterial
A through traffic system across and between urban areas. Allows direct access to adjacent properties, but is characterized by control of entrances, exits, and curb use. (typ. ROW = 100-120’, 4-6 lanes @ 12’w)
Collector Street
This provides for movement of traffic between major arterials and local streets with direct access to adjacent properties. Traffic control is usually provided by signals and stop signs on side streets. (typ. ROW = 60’, 2 (-4) lanes @12’ w)
