highways and highway components highway transportation characteristics
TRANSCRIPT
Highways and Highway Components
Highway Transportation Characteristics
Outline
Functional classification of roadsRoad functionsHierarchical structure of road networksMobility vs. accessibilityMobility vs. transportation mode
Highway componentsCross-sectionsHighway plan and profileInterchangesRural and urban intersections
Road Functions
Mobility
Accessibility
Hierarchical Structure of
Road Networks
Rural
Urban
Mobility vs. Accessibility
Road Class Road Function
Freeways Through movement exclusively
Surface Arterials Through movement primary and some land access
Collectors Traffic movement to higher rank roads, access to abutting properties
Local Roads Access to abutting land and local traffic movement
Hierarchical Structure of
Road Networks
Mobility vs. Accessibility
Mobility vs. Transportation Mode
Mobility vs. Transportation ModeCapacity
capacity in veh/h =
capacity in veh/h/lane x number of lanes
capacity in persons/h =
capacity in veh/h x average vehicle occupancy
Mobility vs. Transportation ModeCapacity
Persons/hrVehicles/hrFacility6,000 x 1.7 = 10,2002,000 x 3 = 6,000Three-lane urban freeway
2,400 x 1.7 = 4,080800 x 3 = 2,400Three-lane urban arterial
100 x 80 = 8,000100 x 1 =100One lane of buses
19,000One track of light rail
40,000One track of heavy rail
Mobility vs. Transportation ModeCapacity
Highway ComponentsCross-section
Highway Components
Highway plan and profile
Highway Components
Urban Intersections
Picture
Highway Components Rural Intersections
Picture
Highway Components
Interchanges
DiamondCloverleaveUrban directional