traffic engineering

this is a brief introduction to various traffic engineering basic characteristics which are useful in designing any corridor or passage with safety & reliability.

1. BHAGWAN MAHAVIR COLLEGE OF ENGINEERING AND TECHNOLOGY Department of Civil Engineering

2. Semester : BE - 5 th Civil-A Subject : Highway Engineering Code : 2150601 Presentation On : Traffic Engineering Prepared by : Eddy Ankit Gangani [email protected]

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

4. What Is Traffic Engineering ? 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. Scope Of Traffic Engineering Traffic Characteristics Traffic studies & analysis Traffic operation – control Planning & Analysis Geometric Design Administration & Management

6. Traffic System Components 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,Reaction time Temporary- Fatigue,Alchohol,Illness,Drugs Traffic Stream Facilities Atmosphere Locality Physical Mental Psychological Environmental Attentiveness Fear Anger Superposition Knowledge Skill Experience Intelligence Literacy

8. Road User Characteristics Physiological–Measurable and Usually Quantifiable 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. Visual Acuity factors Field of Vision : 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. PRT/PIEV Theory Perception-Reaction Time : 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. Vehicular Characteristics Vehicle Categories : 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. Vehicle Characteristics Braking and deceleration Acceleration Low-speed turning characteristics High-speed turning characteristics Size = Height*Width*Length Weight Sight Distance Super Elevation Curves Capacity

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

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

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

17. Road Characteristics-Friction 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

18. A . Q ?? & Q ?

19. Thank You ……