ACCESS CONTOL AND ACCESS
MANAGEMENT
ACCESS CONTROL
 A regulating access
 Advantage of providing access control
is the management of the interference
with the traffic
 Access control techniques can be
implemented with two basic legal
powers:
1. Police Power
2. Eminent Domain
 Access management involves providing
access to land development while
preserving the flow traffic in terms of
capacity, speed and low crash
frequency and severity.
FULL CONTROL ACCESS
 Preference is given to "through traffic"
by providing access connections by
means of ramps with only selected
public roads and by prohibiting crossings
at grade and direct private driveway
connections.
ELEMENTS OF ACCESS MANAGEMENT
 Defining allowable access and access
spacing for highways
 Providing a mechanism for granting
variances
 Enforcing policies and decisions
PRINCIPLES OF ACCESS MANAGEMENT
TECHNIQUES
 Classify road system by primary
function of each roadway (freewaysemphasize movement and provide
complete control of access)
 Limit direct assess to roads with higher
functional classifications
 Locate traffic signals to emphasize
through traffic movements
 Locate driveways and major entrances
to minimize interference with traffic
operations
 Use curbed medians and locate
median openings to manage access
movements and minimize conflicts.
ACCESS CLASSIFICATIONS
 is the foundation of a comprehensive
access management program
 relates the allowable access to each
type of highway (by: purpose,
importance
and
functional
characteristics)
 defines the type and spacing of
allowable access for each class of road.
METHODS OF CONTROLLING ACCESS
 Control by the transportation agency
 Land-use ordinances(Land-use control
is normally administered by local
governments.)
 Geometric design (the use of raisedcurb medians, the spacing of median
openings, use of frontage roads,
closure of median openings, and
raised-curb
channelization
at
intersections, all assist in controlling
access)
 Driveway regulations (guidelines,
regulations, or ordinances, provided
specific statutory authority exists)
PEDESTRIAN
GENERAL CONSIDERATIONS
 Pedestrian facilities include sidewalks,
crosswalks, traffic control features,
and curb cuts (depressed curbs and
ramped sidewalks) and ramps for the
older walkers and persons with
mobility impairments.
 Pedestrians also have a basic
resistance to changes in grade or
elevation and tend to avoid using
special
underpass or overpass
pedestrian facilities
The following have been suggested as
measures with the potential to aid older
pedestrians and road users:
 Use simple designs that minimize
crossing widths and minimize the use
of more complex elements
 Assume lower walking speeds
 Provide median refuge islands of
sufficient width at wide intersections.
 Provide lighting and eliminate glare
sources at locations that demand
multiple information gathering and
processing.
 Consider the traffic control system in
the context of the geometric design to
provide compatibility and adequate
advance warning or guide signs for
situations that could surprise older
drivers or pedestrians or increase their
crash frequencies.
 Use enhanced traffic control devices.
 Provide oversized, retro-reflective
signs with suitable legibility.
 Consider increasing sign letter size and
retro-reflectivity to accommodate
individuals with decreased visual acuity.
 Use properly located signals with large
signal indications.
 Provide enhanced markings and
delineation.
 Use repetition and redundancy in
design and in signing.
WALKING SPEEDS
 Walking speeds are faster at mid-block
locations than at intersections, are
faster for men than for women, and
are affected by steep grades.
 Walking speeds decrease as the
pedestrian density of the walkway
increases.
The following measures may help reduce
pedestrian-vehicular conflicts and improve
operations on urban highways:
 eliminate left and/or right turns
 prohibit
free-flow
right-turn
movements
 prohibit right turn on red
 convert from two-way to one-way
street operation



provide separate signal phases for
pedestrians
eliminate selected crosswalks, and
provide
for
pedestrian
grade
separations
Improvements such as the following can
reduce the frequency of crashes on a
street or highway and provide for bicycle
traffic:
 paved shoulders
 wider outside traffic lanes (4.2 m [14 ft]
minimum), if no shoulders exist
 bicycle-compatible drainage grates
 adjusting manhole covers to the grade
 maintaining a smooth, clean riding
surface
ROADWAY DESIGN
 Roadways should be designed to
reduce the need for driver decisions
 The most significant design factor
contributing to low crash frequencies
for roadways is the provision of full
access control (Full access control
reduces the number, frequency, and
variety of events which drivers
encounter.)
 Road design concerns the outline and
design for a road construction project
 It includes 2D and 3D schematic
drawings
and
renderings,
recommendations for construction
materials, a detailed survey of the
project site, and a plan for the road
construction process.
TRAFFIC CONTROL DEVICES
 The various aids and devices used to
control, regulate and guide traffic.
 Traffic control devices direct, guide,
and inform drivers by offering visual or
tactile indicators.
FOUR MAIN CATEGORIES OF DEVICES
 Signs
 Signals
 Road design and marking
 Barriers and channelizers (island)
KEY RESOURCES AVAILABLE TO ASSIST
HIGHWAY AGENCIES IN MANAGING AND
IMPROVING SAFETY
● NCHRP Report 500 series
● AASHTO Highway Safety Manual (HSM)
● NCHRP
PROJECT DEVELOPMENT PROJECT
 Provides a method that may be used
by highway designers to develop
quantitative
estimates
of
the
differences between potential design
alternatives in crash frequency and
severity
Step 1: Planning Studies
Step 2: Environmental Study
Step 3: Funding Process
Step 4: Final Design
Step 5: Implementation