The document is a presentation on traffic engineering, outlining its importance in ensuring safe and efficient traffic flow for both vehicles and pedestrians. It covers various aspects including traffic characteristics, user and vehicle specifics, and the factors influencing driver behavior and vehicle performance. Key components discussed include the perception-reaction time, road user types, and vehicle categories which impact overall traffic management.

2. Semester : BE - 5th Civil-A
Subject : Highway Engineering
Code : 2150601
Presentation On : Traffic Engineering
Prepared by : Eddy Ankit Gangani
eddygangani@gmail.com

3.  What isTraffic Engineering ?
 Scope of traffic Engineering
 Traffic System Components
 Traffic Characteristics – Road User Characteristics
Vehicular Characteristics
Road Characteristics

4.  Traffic Engineering : It is
very important that traffic
flow on roads should be
efficient-safe-rapid.
 Traffic Engineering is the
branch which deals with
science of measuring
traffic ,Designing &
Operating system to
achieve Safe& efficient
movement of persons as
well as goods.

5.  TrafficCharacteristics
 Traffic studies & analysis
 Traffic operation – control
 Planning & Analysis
 Geometric Design
 Administration & Management

6.  Road users-drivers, pedestrians, bicyclists, and
passengers
 Vehicles
 Streets and highways
 Traffic control devices
 The general environment

7. Traffic Characteristics
Road User
Characteristics
Vehicular
Characteristics
Permanent-
Vision,Hearing,Re
action time
Temporary-
Fatigue,Alchohol,Illn
ess,Drugs
Traffic Stream
Facilities
Atmosphere
Locality
Physical Mental Psychological Environmental
Attentiveness
Fear
Anger
Superposition
Knowledge
Skill
Experience
Intelligence
Literacy

8.  Physiological–Measurable and UsuallyQuantifiable
 Psychological–Much more difficult to measure and quantify
 • Psychological : Desired speeds
Desired safety distances
 • Physiological : Perception-Reaction time
Visual factors
Hearing
 The traffic engineer must deal with elderly drivers as well as 18-year-olds, aggressive drivers
and timid drivers, and drivers subject to myriad distractions both inside and outside their
vehicles.

9.  Field ofVision :The most
important characteristic of
drivers is their ability to see!
 Traffic Signs: Location,
Height, Shapes, Colors
 The peripheral vision field
narrows, as speed increases,
to as little as 100° at 20 mi/h
and to 40° at 60 mi/h.

10.  Perception-ReactionTime : The second critical driver characteristic is
perception-reaction time (PRT).
 Detection. In this phase, an object or condition of concern enters the
driver’s field of vision, and the driver becomes consciously aware that
something requiring a response is present.(Perception=VisionAwareness)
 Identification. In this phase, the driver acquires sufficient information
concerning the object or condition to allow the consideration of an
appropriate response.(Intellection- Interpretation)
 Decision.Once identification of the object or condition is sufficiently
completed, the driver must analyze the information and make a decision
about how to respond.
 Response. After a decision has been reached, the response is now
physically implemented by the driver.(Volition= physical response)
 d = 0.278 S.t

11. Traffic Characteristics
Road User
Characteristics
Vehicular
Characteristics
Dimensions
Weight
Maximum
Turning
Radius
Speed
Acceleration
Braking System
Lighting System
Vehicle Design
Tyre
Static Dynamic

12.  VehicleCategories : AASHTO - Four main
categories
 Passenger type-all passenger cars, SUVs, minivans,
vans, and pickup trucks.
 Buses-intercity motor coaches, transit buses, school
buses, and articulated buses
 Trucks-single-unit trucks, tractor-trailer, and
tractorsemi-trailer combination vehicles
 ▫ Recreational vehicles-motor homes, cars with various
types of trailers (boat, campers, motorcycles, etc.)

13.  Braking and deceleration
 Acceleration
 Low-speed turning characteristics
 High-speed turning characteristics
 Size = Height*Width*Length
 Weight
 Sight Distance
 Super Elevation
 Curves
 Capacity

14.  • High-speed turning characteristics
 S : Speed km/h
 R : Curve Radius m
 e : Super elevation rate %
 f : Coefficient of side friction

15.  Braking and deceleration
 Acceleration
 Low-speed turning characteristics
 High-speed turning characteristics
 Size = Height*Width*Length
 Weight
 Sight Distance
 Super Elevation
 Curves
 Capacity

16.  Friction – Skid + Slip
 Unevenness
 Light Reflecting Characteristics

17.  Skid : vehicle slide without revolving
 Slip : wheel revolves more than longitudinal
distance along the road.(acceleration)
 Factors affecting :
Type of Pavement
Roughness of surface
Dry-wet-smooth pavement conditions
Conditions of tyres
Speed of vehicles
Brake efficiency