EJM – 088
*EJM088*
I Semester M.E. (Civil) Degree Examination, March 2013 Highway Engineering 2K8HW 103 : TRAFFIC ENGINEERING Time : 3 Hours
Max. Marks : 100
Note : 1) Answer any five full questions. 2) Additional data if any may be suitably assumed and stated. 1. a) Explain the concept of Passenger Car Unit (PCU) and factors affecting PCU values. Tabulate the PCU equivalency factors for different vehicle types on urban roads (as per IRC). 10 b) An impatient car driver stuck behind a slow-moving truck travelling at 20 Kmph decides to overtake the truck. The accelerating characteristic of the car is given by : 10 dv/dt = 3.6 – 0.17v where, v is the speed (m/sec) and t is the time (sec). Find a) What is the acceleration after 2, 5, 10 and 30 seconds ? b) What is the maximum speed attainable by the car ? c) How far will the car travel in 30 seconds ? 2. a) What are the objectives of carrying traffic volume studies ? Briefly explain the various automatic traffic volume count methods. 10 b) A 7 day traffic volume count survey conducted during December month at two toll plaza location along a National Highway which are 70 km apart reveals the following traffic flow (ADT). 10
MAV > 6 Axles Heavy Construction Vehicle
MAV upto 6 Axle
3AT
2AT
LGV
Goods Vehicle
Pvt. Bus
Govt. Bus
School Bus
Mini Bus
Location
Car/Jeep/Van
Bus
Total Veh.
Toll Plaza 2880 175 10 1 (ADT)
980 570 1450
2520 4530
520
10
5
13650
Toll Plaza 2000 100 10 2 (ADT)
625 335 1260
2280 4435
535
5
5
11590
Using Monthly fuel sale (Refer Table Q2 (b), tabulate seasonal correction factors for various months and Estimate AADT at this location.
P.T.O.
EJM – 088
*EJM088*
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3. a) Briefly outline the application of spot speed data in traffic engineering. Explain the following methods of measuring spot speeds : i) Enoscope method ii) Radar Speed meters 10 b) The consolidated data obtained from spot speed studies at a section of highway are given below. Plot the frequency distribution and cumulative distribution curves and find the modal speed, upper speed limit and speed value for checking geometric design requirements. 10
Speed range, Kmph
No. of vehicles observed
Speed range, Kmph
No. of vehicles observed
0−10
14
50−60
301
10−20
28
60−70
209
20−30
88
70−80
71
30−40
115
80−90
25
40−50
255
90−100
07
4. a) Briefly outline the uses of carrying out speed and delay studies. Explain the procedure of carrying out speed and delay studies using “Moving Observer Method”. b) Twenty five spot speed observations were taken and were as under :
8 6
52,45,64,54,46,35,78,59,44,56,42,57,41,60,36,64,35,59,47,44,62,46,58,42,45. Calculate :
i) Time-Mean Speed ii) Space-Mean Speed. Verify the relationship between time mean speed and space mean speed.
c) In connection with a survey for determining the spot speed at a given location of a highway, it is desired to obtain the average speed within 2.5 Kmph with a probability of 0.95. Previous studies have indicated that the standard deviation of the speeds is 8.5 Kmph. What size of sample should be selected ? (Take the standard variable associated with a probability of 0.95 as 1.96).
6
*EJM088*
EJM – 088
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5. a) What are the objectives of conducting Origin and Destination Studies ? Explain Home Interview method of conducting O&D survey.
10
b) Give the following mean data from six runs by the floating car method on a 2.5 km section. Determine the average values of volume, journey speed and running speed of the traffic stream along either direction.
10
Journey Time
Stopped Delay
Min
Min
Overtaking
Overtaken
Vehicles in the opposite direction
North Bound
3.15
0.25
25
35
145
South Bound
3.45
0.35
30
27
97
Trip Direction
Vehicles in the same direction
6. a) Explain the following : i) On-Street Parking ii) Off-Street Parking b) Explain the various “3-Es” measures for the reduction in accident rate. 7. a) With sketches explain Channelized intersection and Rotary intersection.
10 10 10
b) At a right angled intersection of two roads, Road 1 has four lanes with a total width of 12.0 m and Road 2 has two lanes with a total width of 7.2 m. The volume of traffic approaching the intersection during design hours are 925 and 750 PCU/hour on the two approaches of Road 1 and 290 and 190 PCU/ hour on the two approaches of Road 2. Design the signal timings as per IRC guidelines.
10
EJM – 088
*EJM088*
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8. Write short notes on any four of the following :
(4×5 each = 20)
i) Importance of vehicular characteristics in traffic engineering ii) Objectives and Scope of Traffic Engineering iii) Warrants for provision of Interchange iv) Principles of traffic signing v) Design factors of highway lighting Table for Q 2(b) Monthly Fuel sale (in litres) in the Project Influence Area Month
Indian Oil, Km. 20
Hindustan Petroleum, Km. 45
Bharat Petroleum, Km. 65
Petrol
Diesel
Petrol
Diesel
Petrol
Diesel
April
4000
38000
9000
97000
13000
321000
May
4000
37000
11000
124000
14000
378000
June
4000
43000
7000
95000
9000
360000
July
4000
67000
6000
90000
8000
194000
August
5000
70000
7000
146000
8000
182000
September
4000
58000
10000
187000
7000
293000
October
4000
35000
12000
183000
10000
220000
November
5000
55000
10000
120000
5000
181000
December
5000
66000
10000
128000
4000
198000
January
3000
56000
8000
133000
0
178000
February
3000
35000
6000
113000
0
146000
March
4000
44000
7000
144000
0
132000
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