Traffic Engg(Traffic Sign & Intersection).pptx

Highway engineering

1. TRAFFIC ENGINEERING HIGHWAY ENGINEERING (2150601) Prepared By: Prof. Sadanand Sahu DEPARTMENT OF CIVIL ENGINEERING GUJARAT POWER ENGINEERING & RESEARCH INSTITUTE, MEHSANA

2. TRAFFIC CONTROL DEVICES 1. Signs 2. Signals 3. Marking 4. Traffic Islands

3. 1. Signs The government of Gujarat has adopted various traffic signs prepared by IRC. As per IRC, there are three types of traffic signs. A. Regularity or Mandatory signs. B. Warning Signs. C. Informatory signs.

4. A. Regularity or Mandatory signs Regularity or Mandatory signs are meant to inform road users of certain laws, regulation and prohibition; the violation of this signs is a legal offence.

5. B. Warning Signs Warning signs are used to warn the road users of certain hazardous conditions that exist on the roadway.

6. C. Informatory Signs These signs are used to guide road users along routes, inform them of destination and distance and provide with information to make travel easier, safe and pleasant. These signs are placed at distance 0.6 m from the kerb and at 2.0 to 3.0 m from the edge of carriage way in case of roads without kerb.

7. Route marker signs: The design of route marker signs for NH has been standardised in India by the IRC. It consists of a shield painted on rectangular plate 450X660 mm. The signs has yellow background and all letters, sign and border painted in black.

8. 2. Signals Traffic signals are provided at road intersection. The main requirements of traffic signals are to draw attention , provide meaning and time to respond and to have a minimum waste of time . Red : Vehicles must stop. Yellow : Lights about to change. Green :Vehicles can proceed.

9. Advantages: Reduce certain types of accidents. Improve safety and efficiency of movement of vehicles. More economical than manual control. Disadvantages : The rear end collision may increase. Improper design and location of signals may lead to violations of control system. Failure of the signal due to electric power failure or any other defect may cause confusion to the road users.

10. Types of Traffic Signals Traffic control signals. Fixed time signals. Manually operated signals. Automatic signals. Pedestrian signals. Special traffic signals.

11. 3. Marking Road marking are the lines, patterns, words, symbols or reflectors on the pavement, kerb, sides of islands or on the fixed objects within or near the roadway. Markings are for control , warning and guidance of road users. IRC standardized these marking (IRC:35-1970). Various types of marking are, Pavement marking. Kerb marking. Object marking. Reflector unit marking.

12. 1) Pavement Marking Pavement or carriage way markings may generally be of white paint. Yellow colour marking are used to indicate parking restriction and for continuous centre line marking. Various pavement marking are: Centre line. Lane line. Stop line. Cross walk lines. Parking space limits.

13. Centre line: These are meant to separate the opposing streams of traffic on undivided tow-way roads on NH and SH, with two or three lanes. single broken line of width 0.1 m and 3.0 m segments and 4.5 m gaps may be painted on straight stretches. b) Lane lines: These marking divide the carriage way into separate lanes on either side of the centre line. These help to guide the traffic and regulate it.

14. c) Stop lines: These are meant for vehicles to stop near the pedestrian crossing, signalized intersection etc. where vehicles have to stop and proceed. d) Cross walk lines: These marking are provided at important intersection to facilitate pedestrians to cross a road. The Width of the crossing may be between 2.0 and 4.0 m.

15. 2) Kerb marking Marking on the kerb indicate certain regulations. Marking on the kerb and edges of islands with alternate black and white line increase the visibility from a long distance.

16. 3) Object marking Physical obstruction on or near the roadway are hazardous and hence should be properly marked. Typical obstructions are supports for bridge, level crossing gates, signs and signals, traffic island, narrow bridges etc. 4) Reflector unit marking These are used as hazard markers and guide markers for safe driving during night.

17. Traffic Island

18. 4. Traffic Islands Traffic island are raised areas constructed within the roadway to establish physical channels through which the vehicular traffic may be guided. Function of traffic island: To segregate the pedestrians and vehicles. To separate traffic into specified path. To increase safety. To diverts traffic from obstacles and expedite the traffic flow.

19. Advantages : It provides smooth and controlled traffic flow. It reduces the accident and increases safety. It gives uniform speed of traffic. No need of police control. Disadvantages : It consumes useful traffic area. It increase travel distance. Width of traffic lane decreases.

20. Types of Traffic Island: Divisional Island. Channelizing Island. Pedestrian Loading Island. Rotary Island.

21. 1. Divisional Island These are intended to separate opposing traffic flow on a highway with four or more lanes. Dividing the highway into two one-way roadway, the head on collisions are eliminated. The kerb should be high enough to prevent vehicles from entering into the island.

22. 2.Channelizing Island These are used to guide the traffic into proper channel through the intersection area.

23. Various uses of channelizing island are: The area of possible conflicts between traffic stream is reduced. They are useful when direction of flow is to be changed. They serve as convenient location for other traffic control devices. They serve as refuge islands for pedestrians.

24. 3. Pedestrian Loading Island They are provided at regular bus stops and similar places for the protection of passengers. A pedestrian island at or near a cross walk to aid and protect pedestrian crossing the carriage way may be termed as pedestrian refuse island.

25. 4.Rotatary Island. It is a large central island of a rotary intersection. Various shapes of rotary islands are shown in fig:

26. Various shapes Rotary Island

27. Intersection Intersection  is also commonly known as  crossroad  is any place where two or more than two roads intersect or meet each other. Highway Intersection has a considerable influence on safety and efficiency of traffic movement. Classification of Intersection At grade Intersection Grade separated Intersection ( Interchange )

28. Types of Manoeuvres

29. Forms of Intersection at Grade

30. Unchannelized Intersection

31. Channelized Intersections

32. Rotary Intersection

33. Interchange In a grade separated intersection (interchange) the intersecting roadways are placed at different elevations to allow uninterrupted traffic flow. It may be underpass or over crossing. Various types of Interchanges are: Cloverleaf Interchange Diamond Interchange Rotary Interchange

34. Full- Cloverleaf Interchange

35. Rotary Interchange