Traffic studies
- 2. TOPIC NAME: TRAFFIC STUDIES SUBJECT CODE: 2I70613 BRANCH: CIVIL ENGINEERING PREPARED BY: GUIDED BY: PROF. RAJAN LAD SR NO. NAME ENROLL. NO. 1. PATEL PRASHANT S. 141100106078 2. PATEL TWINKAL D. 141100106092 3. MISTRY ADITYA P. 151103106009 4. PATEL KAJAL M. 151103106011 5. RATNANI MANISHA N. 151103106016
- 3. CONTENT • TRAFFIC STUDY • WHEN SHOULD A TRAFFIC STUDY BE CONDUCTED? • TRAFFIC SURVEY • TRAFFIC VOLUME STUDY – AUTOMATIC COUNTING METHOD – MANUAL COUNTING METHOD 4/9/2018 3GDEC,CIVIL
- 4. TRAFFIC STUDY “A traffic study is a detailed examination and analysis of a transportation system supported by data collection.” Source-Institute of Transportation Engineers
- 5. WHEN SHOULD A TRAFFIC STUDY BE CONDUCTED? • When a new development is proposed and it will generate substantial new traffic; • When financial assessments are implemented (transportation impact fees); • When a major roadway improvement or reconstruction project is proposed; • When a development is proposed for a sensitive area. 4/9/2018 5GDEC,CIVIL
- 6. TRAFFIC SURVEY • Traffic volume study • Speed study • Origin and destination study • Traffic flow characteristics study • Traffic capacity study • Parking study • Accident study 4/9/2018 6GDEC,CIVIL
- 7. TRAFFIC VOLUME STUDY • Traffic volume studies are conducted to determine the number, movements, and classifications of roadway vehicles at a given location. • Volumes of a day or an hour can vary greatly, depending on the different day of the week or different time period of a day. 4/9/2018 7GDEC,CIVIL
- 8. METHODS OF VOLUME STUDY Automatically Contact system based Contactless system based Manually Direct Method Indirect Method 4/9/2018 8GDEC,CIVIL
- 9. AUTOMATIC COUNTERS • Automatic counters are also known as mechanical counters . • They can automatically record the total numbers of vehicles crossing a section of the road in desired period of time. 4/9/2018 9GDEC,CIVIL
- 10. AUTOMATIC COUNTERS Advantages • It can work throughout the day and night for desired period, which is impractical in manual. • No need of supervision. • Suitable for long count. Disadvantages • It does not give the detail of the traffic like various classes, stream and turning movement. • It is not possible to record pedestrian traffic. • The impulses caused by light vehicles may not be enough in some cases to acute the counter. 4/9/2018 10GDEC,CIVIL
- 11. AUTOMATIC COUNTING METHOD: CONTACT SYSTEM source-http://lgam.wikidot.com/traffic-counter Pneumatic tube 4/9/2018 11 GDEC,CIVIL
- 12. AUTOMATIC COUNTING METHOD: CONTACTLESS SYSTEM Source-http://www.azcentral.com Radar4/9/2018 12GDEC,CIVIL
- 13. AUTOMATIC COUNTING METHOD: CONTACTLESS SYSTEM • The other contactless method – Photo-electric device – Infra-red device – Magnetic device – Ultrasonic device 4/9/2018 13GDEC,CIVIL
- 14. MANUAL COUNTING METHOD • The manually method is the method in which a group of peoples are trained to record the total numbers of vehicles crossing a section of the road in desired period of time on record sheets manually. 4/9/2018 14GDEC,CIVIL
- 15. MANUAL COUNTING METHOD Advantage • It gives the full detail of the traffic like various classes, stream and turning movement etc of the vehicles. Disadvantage • It cannot work throughout the day and night for all days of year. • It is costly. 4/9/2018 15GDEC,CIVIL
- 16. MANUAL COUNTING METHOD: DIRECT METHOD Hand Counter 4/9/2018 16GDEC,CIVIL
- 17. MANUAL COUNTING METHOD: INDIRECT METHOD • Video cameras are mounted to record the traffic condition on a road. 4/9/2018 17GDEC,CIVIL
- 18. MOVING OBSERVER METHOD • Moving observer method of traffic stream measurement has been developed to provide simultaneous measurement of traffic stream variables. • It has the advantage of obtaining the complete state with just four observers, and a vehicle. Source:-Dr. Tom V. Mathew, IIT Bombay 4/9/2018 18GDEC,CIVIL
- 19. MOVING OBSERVER METHOD • Determination of any of the two parameters of the traffic flow will provide the third one by the equation q = uk • Thus, moving observer method is the most commonly used method to get the relationship between the fundamental stream characteristics. 4/9/2018 19GDEC,CIVIL
- 20. MOVING OBSERVER METHOD AGAINSTWITH 4/9/2018 20GDEC,CIVIL
- 21. MOVING OBSERVER METHOD Consider a stream of vehicles moving in the north bound direction. Two different cases of motion can be considered. The first case considers the traffic stream to be moving and the observer to be stationary. If No is the number of vehicles overtaking the observer during a period of T ,then N0 = q × T 4/9/2018 21GDEC,CIVIL
- 22. MOVING OBSERVER METHOD The second case assumes that the stream is stationary and the observer moves with speed V0. If Np is the number of vehicles overtaken by observer over a length L, then Np = k × L Np = k × V0 × T 4/9/2018 22GDEC,CIVIL
- 23. MOVING OBSERVER METHOD Now consider the case when the observer is moving within the stream. In that case Mo vehicles will overtake the observer and Mp vehicles will be overtaken by the observer in the test vehicle. Let the difference M is given by Mo - Mp, then M = Mo - Mp = q T − k Vo T 4/9/2018 23GDEC,CIVIL
- 24. MOVING OBSERVER METHOD Mw = q Tw − k Vw Tw Ma = q Ta + k Va Ta the test vehicle is run twice once with the traffic stream and another one against traffic stream, so 4/9/2018 24GDEC,CIVIL
- 25. )Ta(Tw MaMwq MOVING OBSERVER METHOD From study; q yTwT 4/9/2018 25GDEC,CIVIL
- 26. MOVING OBSERVER METHOD The data from four moving observer test methods are shown in the table. Column 1 gives the sample number, column 2 gives the number of vehicles moving against the stream, column 3 gives the number of vehicles that had overtaken the test vehicle, and last column gives the number of vehicles overtaken by the test vehicle. Find the three fundamental stream parameters for each set of data. Also plot the fundamental diagrams of traffic flow. take length of stretch is 0.5 km and journey time is 0.025. Numerical Example 4/9/2018 26GDEC,CIVIL
- 27. MOVING OBSERVER METHOD Sample no. X=no. of vehicle moving against traffic Mo no. of vehicle overtaking the test vehicle Mp no. of vehicle overtaken by the test vehicle 1 107 10 74 2 113 25 41 3 30 15 5 4 79 18 9 Samp le no. x mo mp y= mo -mp ta tw q v k 1 107 10 74 -64 0.025 0.025 860 5.03 171 2 113 25 41 -16 0.025 0.025 1940 15.04 129 3 30 15 5 10 0.025 0.025 800 40 20 4 79 18 9 9 0.025 0.025 1760 25.14 70 4/9/2018 27GDEC,CIVIL
- 28. MOVING OBSERVER METHOD 4/9/2018 28GDEC,CIVIL
- 29. PASSENGR CAR UNIT • The different vehicle classes have a wide range of static characteristics such as length, width, etc. and dynamic characteristics such as speed, acceleration, etc. It is difficult to estimate the traffic volume and traffic capacity of road way under mix traffic flow. • It is common practice to consider the passenger car as the standard vehicle unit to convert the other classes vehicle classes and this unit is called PCU. 4/9/2018 GDEC,CIVIL 29
- 30. Factors affecting PCU • Vehicle characteristics • Traffic stream characteristics • Roadway characteristics • Control of traffic 4/9/2018 GDEC,CIVIL 30