2. Controlled access (limitedControlled access (limited
entry and exit)entry and exit)
High speed (up to 65 mph)High speed (up to 65 mph)
Divided by a barrier orDivided by a barrier or
medianmedian
Multiple lanesMultiple lanes
May have minimum speedMay have minimum speed
limitlimit
Only for motorized vehiclesOnly for motorized vehicles
Characteristics of an ExpresswayCharacteristics of an Expressway
3. As speed increases,As speed increases,
Steering input to maneuver the vehicle
DECREASES
The faster you travel the less you
have to steer
4. Cloverleaf InterchangeCloverleaf Interchange
A cloverleaf interchangeA cloverleaf interchange has a series
of entrance and exit ramps that
resemble the outline of a four leaf clover.
allows for the interchange of two
expressways or major roadways.
has shared entrance and exit
weave lanes.
This designThis design
Traffic is permitted to move ONLY in
the direction indicated by the arrows.
5. Diamond InterchangeDiamond Interchange
A diamond interchangeA diamond interchange is designed
to be used when a road with slower
speeds crosses a busy expressway.
Traffic is permitted to move ONLY in
the direction indicated by the arrows.
for the interchange of a major
roadway with a secondary dual or
multiple lane roadway.
This design allows:This design allows:
6. Trumpet InterchangeTrumpet Interchange
A trumpet interchangeA trumpet interchange is used when an
intersecting side road forms a T intersection
with the expressway.
Traffic is permitted to move ONLY in
the direction indicated by the arrows.
This design:This design:
accommodates the T-intersection flow of
traffic at the junction of two roadways.
allows for traffic on a secondary two-way
street to merge onto a multiple lane
roadway.
7. Frontage Road InterchangeFrontage Road Interchange
Frontage Road InterchangesFrontage Road Interchanges allow vehicles
using parallel secondary two-way or one-way
roadways to merge onto a major multiple lane
roadway.
Traffic is permitted to move ONLY in
the direction indicated by the arrows.
drivers to exit a multiple lane roadway and
use the parallel frontage road.
secondary road traffic flows to mix efficiently
with higher speed traffic flows on the multiple
lane roadway.
This design allows:This design allows:
8. Common Expressway SignsCommon Expressway Signs
Interstate signsInterstate signs
Warning signsWarning signs
Guide signsGuide signs
HOV =HOV = Restricted laneRestricted lane
A major contributor to your decision as to how you will maintain a safeA major contributor to your decision as to how you will maintain a safe
path of travel, proper lane position, and your lane choice, is based onpath of travel, proper lane position, and your lane choice, is based on
the information provided by the road signs and lane markings.the information provided by the road signs and lane markings.
9. Entrance RampsEntrance Ramps
Entrance
Ramp
Acceleration
Lane
Merge
Area
Entrance ramps provide one-wayEntrance ramps provide one-way
directional access to an expressway.directional access to an expressway.
The ramp is divided into three sections:The ramp is divided into three sections:
1.1. The Entrance or Access RampThe Entrance or Access Ramp —— gives the
driver time to begin evaluating traffic conditions.
2.2. The Acceleration LaneThe Acceleration Lane —— allows a driver to
adjust vehicle speed to the speed of traffic on the
expressway.
3.3. The Merging AreaThe Merging Area —— allows the driver to merge
onto the expressway.
*Search for: entrance # & direction
wrong way or do not enter signs
10. Use the left-lane signal indicator
Accelerate to the speed of traffic
Monitor gap on expressway
Never STOP!
Acceleration LaneAcceleration Lane
Acceleration LaneAcceleration Lane
11. Reduced Risk Lane ChangesReduced Risk Lane Changes
Entering or exitingEntering or exiting
Allowing anotherAllowing another
driver to enterdriver to enter
Following large orFollowing large or
slow-moving vehiclesslow-moving vehicles
Lane ahead becomesLane ahead becomes
blockedblocked
Being tailgatedBeing tailgated
AnimalsAnimals
PassingPassing
Reasons for changing lanes include:Reasons for changing lanes include:
EntranceEntrance
RampRamp
ExitExit
RampRamp
12. Choosing Lanes at Exit or EntranceChoosing Lanes at Exit or Entrance
Right Lane:Right Lane:
Heavier and slower vehicles
Vehicles entering the expressway
Vehicles getting ready to exit
Left Lane:Left Lane:
Higher speed and passing traffic
Exit / Entry
Right Lane
Center Lane
Left Lane
Center Lane:Center Lane:
Long distance or passing
13. Multiple Lane Roadway ExitMultiple Lane Roadway Exit
An expressway exit has twoAn expressway exit has two
components:components:
1. The Deceleration Lane —1. The Deceleration Lane — gives the
driver the time and space needed to
adjust his/her vehicle’s speed to the
slower posted ramp speed without
disrupting the flow of traffic on the
expressway.
2. The Exit Ramp —2. The Exit Ramp — allows traffic to
enter an adjoining roadway.
Exit
Ramp
DecelerationLane
**Slow down!
14. Potential Exiting ProblemsPotential Exiting Problems
“Weave” lane conflicts
Short deceleration lane
Sharp curve on ramp
Traffic stopped on the exit ramp
There may be a STOPThere may be a STOP
sign or a traffic light atsign or a traffic light at
the end of the exit ramp.the end of the exit ramp.
The driver must adjustThe driver must adjust
from a fast speed to afrom a fast speed to a
STOP in a short distance.STOP in a short distance.
15. Weave LaneWeave Lane
Traffic entering and exiting the expressway uses the same lane.Traffic entering and exiting the expressway uses the same lane.
To avoid a conflict,To avoid a conflict, the driver in thethe driver in the BLUE car entering from thecar entering from the
entrance ramp must yield the right-of-way to the driver in theentrance ramp must yield the right-of-way to the driver in the RED
car who is leaving the expressway (entering yields to exiting).who is leaving the expressway (entering yields to exiting).
Weave Lane
R.O.W. = RED car is already on the road!
16. High Speed ConsiderationsHigh Speed Considerations
1. If you miss your exit on the interstate, you must exit
& re-enter going the correct direction.
2.If you miss your exit, you should continue the next
one.
3.Where are U-turns allowed on expressways?
NO WHERE
4. Pack driving is when vehicles get “bunched up.”
-- Dangerous because driver’s have no space
cushion. No time to avoid crash
5. No space & no escape routes cause chain reaction
collisions.
17. Highway HypnosisHighway Hypnosis
Plan breaks and rest stops to combat
highway hypnosis or go to a safe area
for rest or sleep when tired.
Is a dulled or drowsy condition that can occur when
driving long distances
Situation becomes worse
when the driver’s eyes
focus on the center line.
18. Ramp MeteringRamp Metering
Used to control large volumes of traffic enteringUsed to control large volumes of traffic entering
expresswaysexpressways
Uses a system of lights and sensorsUses a system of lights and sensors
Allows only a few cars at a time to enter congestedAllows only a few cars at a time to enter congested
limited access highwayslimited access highways
19. How does Urban differ from Rural?How does Urban differ from Rural?
A lot more traffic in urban areas.A lot more traffic in urban areas.
Slower speeds, too.Slower speeds, too.
20. Special Roadway ConditionsSpecial Roadway Conditions
Disabled vehiclesDisabled vehicles
Expressways through citiesExpressways through cities
• Don’t be a “rubber necker”
• Give the disabled vehicle plenty of room
• Pull as far off the roadway as possible if
your vehicle becomes disabled
• Avoid driving in the right lane when
vehicles are merging
• Search for signs, signals, and roadway
markings
• Search for exits early and adjust position
in adequate time to exit safely
• Don’t make last minute lane changes to
gain access to an exit
• Monitor the zones around your vehicle
and adjust position to create space cushions
21. Short Trips on ExpresswaysShort Trips on Expressways
Know the name, route, and number
of the
entrance and exit to be used
In VA mile markers = Exit numbers
Take a local map
Plan a time to travel to avoidPlan a time to travel to avoid
congestion around major citiescongestion around major cities
22. Identify theIdentify the ExitExit EarlyEarly
Exits are marked with guide signs,
usually one to two miles before the
exit.
You can determine if an exit is a right
exit or a left exit by the position of the
exit number on the sign. So, Exit 45A
is a right exit, because in this picture
the exit number on the upper right-
hand side of the sign.
In Virginia, exit numbers correspond
with mile marker numbers.
About one-half mile (20- to 30-
seconds) before the exit, signal and
move to the lane closest to the
deceleration lane.
23. Multiple Lane Roadway DangersMultiple Lane Roadway Dangers
Vehicles moving onto the shoulderVehicles moving onto the shoulder
or re-entering the roadwayor re-entering the roadway
Tires losing traction and hydroplaningTires losing traction and hydroplaning
during wet weather conditionsduring wet weather conditions
Slow moving vehicles ahead or “PackSlow moving vehicles ahead or “Pack
Driving”Driving”
Two vehicles changing lanes at theTwo vehicles changing lanes at the
same time into same lanesame time into same lane
Windy and/or wet sections of the roadwayWindy and/or wet sections of the roadway
