assignment problems traffic engineering & management ... · pdf fileassignment problems...
TRANSCRIPT
![Page 1: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/1.jpg)
Assignment problems
Traffic Engineering & Management (ElectiveII)
Solve any three questions [for choosing 3 questions, generate 3 random numbers using your
roll number, the random number must lie between 1 and 70]
1. An observer standing beside a road starts counting vehicle passing him from 4pm to 4:20pm
and he counts about 580 vehicles. What is the average time headway. An aerial photograph
of a stretch of a road of about 200 meter shows the presence of 40 vehicles. What is the
average spacing.
2. If an observer standing beside a road noted that the vehicles are passing him every 3
seconds. If so what is the flow rate.
3. Derive the relationship between fundamental parameters of traffic with a detailed
illustration of fundamental diagrams of traffic flow.
4. Derive the relationship between the time mean speed and space mean speed. Verify the
above relation using some hypothetical speed data expressed in a frequency table.
5. Verify the relationship between the time mean speed and space mean speed using some
hypothetical speed data generated by you (about 20-30 spot speeds) and represented in a
frequency table.
6. Calculate the time mean speed and the space mean speed of the following observation.
Speed
Range
Volume
(m/sec) (veh/hr)
10-12 12
![Page 2: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/2.jpg)
12-14 18
14-16 24
16-18 20
18-20 14
7. Determine the time mean speed and space mean speed from the following data. Verify the
relationship between them.
Speed m/s Frequency
1-5 2
![Page 3: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/3.jpg)
6-10 5
11-15 7
16-20 9
8. The following travel times in seconds were measured for vehicles as they traversed a 3 km
segmeny of a highway.
Compute the time mean speed and space mean speed for this data. Why space mean speed is
always lower than time mean speed, explain with a derivation.
9. Calculate the time mean speed and the space mean speed of the following spot speed data:
Speed Range Volume
![Page 4: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/4.jpg)
(m/sec) (veh/hr)
10-12 12
12-14 18
14-16 24
16-18 20
18-20 14
10. For the data given below,compute the time mean speed and space mean speed. Also verify
the relationship between them. Finally compute the density of the stream.
![Page 5: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/5.jpg)
speed range frequency
1-4 2.5
5-8 6.5
9-12 10.5
13-16 14.5
17-20 18.5
11. Illustrate neatly on a single graph the speed-density relation by Greenberg, Greenshield,
Underwood, Pipe(n=0.5,2), two regime, and three regime models, along with typical field
observations
12. Explain with neat sketch the need and examples of multi-regime stream models.
![Page 6: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/6.jpg)
13. Sketch the three fundamental diagrams of traffic flow. Derive the relation between
maximum flow ( ), jam density ( ), and free flow speed ( ). Assume liner speed
flow relation: .
14. Plot typical speed-density field data points. Draw the shapes of various traffic stream
models (5-7) including multi-regime models. Write the equations of these models as well.
15. In a traffic study, the observed densities were 150, 120, 50, 70 and 20 veh/km and the
corresponding speeds were 10, 25, 45, 40 and 32km/h. Find the jam density according to
Greenberg's logarithmic traffic stream model. (Hint: Linearize the expression)
16. For the following data on speed and concentration, determine the parameters of
Greenshields' model. Find the concentration corresponding to a speed of 40 kmph. Find also
the maximum flow.
Concentration(veh/km) Speed(kmph)
180 4
140 20
30 50
![Page 7: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/7.jpg)
75 35
17. A study of flow at a particular location resulted in a calibrated speed-density relationship as
follows. . For this relationship, determine free flow speed,
jam density, maximum flow, and the relationship between fundamental parameters of
traffic. (Illustrate with a sketch)
18. If the mean speeds in kmph observed from a road stretch at various time is given as: 10,
25, 45, 40, and 50, and the corresponding densities in veh/km are: 150, 120, 50, 70, and 20.
What would be the maximum flow on this road stretch.
19. Determine the parameters of Greenshields model for the following data. Find the
maximum flow and density for a speed of 45 kmph.
Speed (kmph) Density (veh/km)
5 150
20 120
30 100
![Page 8: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/8.jpg)
40 70
20. A study of flow at a particular location resulted in a calibrated speed-density relationship as
follows.
For this relationship, determine free flow speed, jam density, maximum flow, speed-flow
relationship, and flow-density relationship. (Illustrate with a sketch)
21. In a traffic study experiment, density values are obtained as 160, 120, 40, and 72 veh/km
corresponding to speed values of 3, 18, 55, 32 respectively. Determine the parameters of
Greenshields' model. Find the density corresponding to a speed of 40 kmph. Find also the
maximum flow.
22. The following speed and density is observed from a road section. If we assume the speed
decreases linearly with respect to density, then: (a) what will be the density at a speed of 10
kmph, and (b) what will be the maximum flow across the section
Speed (kmph) Density (veh/km)
5 120
20 90
![Page 9: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/9.jpg)
30 40
40 10
23. The speed and density observed from a road is given below. What is the density and flow
corresponding to a speed of 25 kmph. State the assumptions/model used in the computation.
Speed (kmph) Density (veh/km)
10 200
20 170
30 120
![Page 10: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/10.jpg)
40 100
1. Derive the equation for flow ( ) from the moving observer method.
24. (a) Derive the expression for flow across a section of road by moving car method. (b) Prove
that this formulae actually estimates the stream flow.
25. Derive expression for the fundamental parameters of traffic flow by moving observer
method (10)
26. In a traffic stream, 30% of the vehicles travel at a constant speed of 60km/h, 30% at a
constant speed of 80km/h, and the remaining vehicles at a constant speed of 100km/h. An
observer travelling at a constant speed of 70km/h with the stream over a length of 5km is
overtaken by 17 vehicles more than what he has overtaken. The observer met 303 vehicles
while traveling against the stream at the same speed and over the same length of highway.
What is the mean speed and flow of the traffic stream?
27. Two friends were traveling from Mumbai to Pune and have decided to count the vehicles
on a short stretch of 5 km. The first one sat on the left side and counted vehicles passed by
him. The second sat on the right side and counted vehicles overtaken him. They counted 20
and 60 respectively while traveling at 30 kmph. They did the same exercise on the next day
about same time and counted 25 and 40 respectively and were traveling at 35 kmph.
Assuming same traffic conditions on both days, compute the density, mean speed, and flow
on that stretch.
28. The observations from a moving car method are given below. Assuming linear speed-
density relation, what is the maximum flow, speed, and density the following following
stretch can take. Show the details of the calculation
Overtaken by
the test
vehicle
Overtaking the
test vehicle
Moving
against
traffic
Travel
time with
the
Travel
time
against
the traffic
![Page 11: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/11.jpg)
stream traffic (s) (s)
5 119 618 422 268
26 12 389 213 188
24 9 401 226 396
2 55 410 274 255
26 9 374 226 396
29. A moving vehicle experiment was conducted on a 2.5 km section of a highway. Two trials
were conducted in the direction of dominant traffic flow. In the first trial, number of
vehicles that had overtaken the test vehicle is 30, number of vehicles overtaken by the test
vehicle is 6, and test vehicle speed is 30 kmph. In the second trial, number of vehicles that
had overtaken the test vehicle is 20, number of vehicles overtaken by the test vehicle 26,
and test vehicle speed is 35 kmph. Calculate the fundamental parameters of traffic flow and
the average headway and spacing.
![Page 12: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/12.jpg)
30. A person walking from office on a one-way street takes 60 min to get home, of which 12
min was taken talking to the driver of a stalled vehicle. He counted 52 vehicles while he
was walking and 25 vehicles while he stopped. What are the travel time and flow of the
vehicle stream? (7)
31. A student riding his bicycle from campus on a one-way street takes 50 min to get home, of
which 10 min was taken talking to the driver of a stalled vehicle. He counted 42 vehicles
while he rode his bicycle and 35 vehicles while he stopped. What are the travel time and
flow of the vehicle stream? (6)
32. Determine the time mean speed, space mean speed, and percentile speed from the
following speed (in m/s) data.
Speed Frequency
1- 5 9
6-10 16
11-15 32
16-20 48
![Page 13: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/13.jpg)
21-25 23
26-30 9
33. For a given road following speed data is collected. 25, 31, 36, 39, 42, 44, 47, 48, 49, 51, 52,
52, 53, 54, 55, 56, 57, 57, 57, 58, 59, 60, 60, 62, 63, 64, 65, 66, 66, 68, 68, 69, 70, 70, 71,
73, 75, 79, 85, 89, 90. What is the speed you will recommend for designing sight distance or
radius of circular curve?
34. The spot speeds of ten vehicles observed at a certain location are 55.1, 40.8, 32.2, 47.8,
64.5, 53.2, 58.2, 67.6, 36.4, and 53.2 kmph. Find the time mean speed, space mean speed
and 85th percentile speed
35. Plot the cumulative frequency distribution curve for the following data and show the 85th
percentile speed
Speed Range Frequency
20-30 8
30-40 43
![Page 14: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/14.jpg)
40-50 35
50-60 29
60-70 11
70-80 4
36. (a) Derive the relationship between time mean speed and space mean speed. (b) Write the
probability density function for normal distribution and Parson type III distribution and its
special cases with various notations used.
37. An observation of headways for 800 samples is given below. Mean headway and standard
deviation observed are 2.76 and 1.79. Fit Pearson type III distribution if the shift parameter
is 0.5.
t
Observed Proportion
![Page 15: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/15.jpg)
0.0 1.0 191
1.0 2.0 131
2.0 3.0 170
3.0 4.0 98
4.0 5.0 82
5.0 6.0 81
6.0 7.0 44
![Page 16: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/16.jpg)
7.0
2
38. An observer counts 300 vehicles in an hour at a location. Assuming that the vehicle arrival
follows Poisson distribution: (i) estimate the probability of a pedestrian getting a gap of at
least 5 seconds; and (ii) estimate how many vehicles will be generated in two minutes
(Assume 20 second interval and use the following random numbers: 0.60, 0.42, 0.54, 0.48,
0.69, 0.42)
39. Using the following random numbers generate vehicle arrival for a period of 20 sec.
Assume headways to follow exponential distribution with mean time headway 6
sec.
40. At a particular section on a highway the following headways are observed: 0.04, 1.37, 1.98,
5.09, 3.00, 2.32, 2.54, 1.37, 0.94, 1.79, 1.10, 6.24, 4.82, 2.77, 4.82, 6.44. Fit an exponential
distribution and compare the observed and estimated mean. [Assume headway ranges as 0-
2, 2-4, 4-6, and 6-8]
41. A headway survey gave a mean of 3.76 and standard deviation of 1.17. Fit a Pearson type
III distribution and find probability that the headway is between 2 and 4 seconds. Assume a
shift parameter of 0.5 and an interval of 0.5 for calculations.
42. If the flow rate at a given section of road is 1600 and if we assume the inter arrival time of
vehicles follow an exponential distribution, then:
1. the probability of headways greater than 1.8 second
2. the probability of headway between 1.2 and 2.4 seconds
3. the probability of headways less than the mean headway
43. An obseravtion from 3424 samples is given table below. Mean headway observed was 3.5
seconds and the standard deviation 2.6 seconds. Fit a negative exponetial distribution.
Table 1: Obsered headway distribution
0.0 0.5 0.012
![Page 17: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/17.jpg)
0.5 1.0 0.064
1.0 1.5 0.114
1.5 2.0 0.159
2.0 2.5 0.157
2.5 3.0 0.130
3.0 3.5 0.088
3.5 4.0 0.065
4.0 4.5 0.043
4.5 5.0 0.033
5.0 5.5 0.022
5.5 6.0 0.019
6.0 6.5 0.014
6.5 7.0 0.010
7.0 7.5 0.012
7.5 8.0 0.008
8.0 8.5 0.005
8.5 9.0 0.007
9.0 9.5 0.005
9.5
0.033
Total 1.00
44. An obseravtion from 3424 samples is given table below. Mean headway observed was 3.5
seconds and the standard deviation 2.6 seconds. Fit a normal distrbution, if we assume
minimum expected headway is 0.5.
![Page 18: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/18.jpg)
Table 2: Obsered headway distribution
h h+dh
0.0 0.5 0.012
0.5 1.0 0.064
1.0 1.5 0.114
1.5 2.0 0.159
2.0 2.5 0.157
2.5 3.0 0.130
3.0 3.5 0.088
3.5 4.0 0.065
4.0 4.5 0.043
4.5 5.0 0.033
5.0 5.5 0.022
5.5 6.0 0.019
6.0 6.5 0.014
6.5 7.0 0.010
7.0 7.5 0.012
7.5 8.0 0.008
8.0 8.5 0.005
8.5 9.0 0.007
9.0 9.5 0.005
9.5
0.033
![Page 19: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/19.jpg)
Total 1.00
45. An obseravtion from 3424 samples is given table below. Mean headway observed was 3.5
seconds and the standard deviation 2.6 seconds. Fit a Person Type III Distribution.
Table 3: Obtained headway distribution
h h+dh
0.0 0.5 0.012
0.5 1.0 0.064
1.0 1.5 0.114
1.5 2.0 0.159
2.0 2.5 0.157
2.5 3.0 0.130
3.0 3.5 0.088
3.5 4.0 0.065
4.0 4.5 0.043
4.5 5.0 0.033
5.0 5.5 0.022
5.5 6.0 0.019
6.0 6.5 0.014
6.5 7.0 0.010
7.0 7.5 0.012
7.5 8.0 0.008
8.0 8.5 0.005
![Page 20: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/20.jpg)
8.5 9.0 0.007
9.0 9.5 0.005
9.5
0.033
Total 1.00
46. Given the headways observed from a survey is given below. Fit an exponential distribution
and compare the actual and computed mean and standard deviation. 5.15, 1.22, 2.65, 2.35,
0.47, 2.8, 7.67, 4.74, 2.42, 4.87, 5.94, 8.58, 9.74, 0.56, 0.66, 6.72, 7.41, 6.94, 2.42, 5.61
47. The number of vehicles arriving on a single lane highway from one direction in successive
10 seconds intervals is shown below. Fit a poisson distribution to this data and comment on
the results. Plot the observed and modeled values in a graph sheet.
Vehicle arriving 0 1 2 3 4 5 6
in 20s interval
Frequency 17 31 12 24 10 6 0
48. A line of vehicles are in car following mode and all vehicles are travelling at 18 m/s with
distance headway of 20 m. After 1.2 seconds, the lead vehicle suddenly decelerates at a rate
of 1.2 until it stops completely. simulate the behaviour of first following vehicle
using the GM fifth car following model for the first 2.5 seconds. Tabulate the results.
Assume headway exponent 1.2, speed exponent 1.6, sensitivity coefficient 0.8, reaction time
0.6 seconds, and scan interval 0.3 seconds.
![Page 21: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/21.jpg)
49. Simulate the following vehicle behaviour for the following data using Widemann 74
model. (a) For the case of stand still distance 3.5m, additive part of safety distance 1.5, and
multiplicative part of safety distance 0.8. (b) For the case of stand still distance 3.5m,
additive part of safety distance 1.5, and multiplicative part of safety distance 0.8. Comment
on the following vehicle behaviour for the above two cases.
50. A car is travelling with a speed of 16 m/sec at time t=0. Another car follows the first at a
distance of 28 m with same velocity. If the first car accelerated by 1 m/sec from t=1 to 2
and decelerate by 1 m/sec from t=2 to 3, find the speed, acceleration and spacing of the
follower at time t=3.0 sec. Assume the reaction time is 1 sec, vehicle dynamics are updated
every 0.5 seconds, and the car following model is given by Eq. 1. (Use of a tabular form is
encouraged).
(1)
51. In a simulation experiment on a single lane road, one vehicle is travelling at 18 . After
1.5 seconds, the vehicle suddenly accelerates at a rate of for the next 1.8
seconds. Simulate the behaviour of subsequent vehicle with an initial speed of 16 m/s using
GM fifth car following model for the first 3 seconds if the initial distance headway is 20
. Tabulate the results. Assume headway exponent 1.2, speed exponent 1.5, sensitivity
coefficient 0.8, reaction time 0.6 seconds, and update interval of 0.3 seconds.
52. A line of vehicles are in car following mode and all vehicles are travelling at 15 m/s with
distance headway of 20 m. After 1.2 seconds, the lead vehicle suddenly decelerates at a rate
of 1.2 until it stops completely. simulate the behaviour of first following vehicle
using the GM fifth car following model for the first 2.5 seconds. Tabulate the results.
Assume headway exponent 1.2, speed exponent 1.6, sensitivity coefficient 0.6, reaction time
0.6 seconds, and scan interval 0.3 seconds.
53. In a simulation experiment on a single lane road, one vehicle is travelling at 16 . After
0.6 seconds, the vehicle suddenly accelerates at a rate of for the next 0.9
seconds. Simulate the behaviour of subsequent vehicle with an initial speed of 16 m/s using
GM fifth car following model for the first 2.1 seconds if the initial distance headway is
![Page 22: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/22.jpg)
25 . Tabulate the results. Assume headway exponent 1.2, speed exponent 1.4, sensitivity
coefficient 0.6, reaction time 0.6 seconds, and update interval of 0.3 seconds.
54. A line of vehicles are in car following mode and all vehicles are travelling at 15 m/s with
distance headway of 25 m. After 1 second, the lead vehicle suddenly decelerates at a rate
of until it stops completely. Simulate the behaviour of first following vehicle
using the GM fifth car following model for the first 3 seconds. Tabulate the results. Assume
headway exponent 1.0, speed exponent 1.5, sensitivity coefficient 0.5, reaction time 0.5
seconds, and scan interval 0.25 seconds.
55. A roadway has 3 lanes. A vehicle is travelling in the middle lane (i.e., 2nd ) and has the
options of either travelling in the same lane or changing either to the 1st or 3rd lanes. These
decisions are governed by the utlities of the lanes ( ) and gaps ( ) . If the vehicle has
decided to leave the current lane, the decisions of choosing among the other two lanes are
governed by the utilities of gaps ( ) in those lanes. On which lane would the vehicle like
to travel
probably?
Lane No. Relative speed
(m/s)
Front gap
(m)
Lead gap
(m)
Lag gap
(m)
1 5 8 5 3
2 3 - - -
![Page 23: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/23.jpg)
3 8 - 9 6
56. In a case study, the average travel time for a particular stretch was found out to be 22.8
seconds, standard deviation is 5.951 and model time step duration is 10 sec. Find out the
Robertson’s model parameters and also the flow at downstream at different time steps
where the upstream flows are as follows
57. A 6 km undivided four lane highway on level terrain has free flow speed of 75 kmph. The
lane width is 3.5m with peak hour volume of 1600 veh/hr and 12% trucks and buses, 2%
Recreational vehicles. Find the capacity and level of service. Assume peak hour factor 0.9.
58. A segment of undivided four-lane highway on level terrain has field-measured FFS 74.0-
km/h, lane width 3.4-m, peak-hour volume 1,900-veh/h, 13 percent trucks and buses, 2
percent RVs, and 0.90 PHF. What is the peak-hour speed, and density for the level terrain
portion of the highway? ( and )
59. Consider an existing four lane free-way in rural area, having very restricted geometry with
rolling terrain. Peak hour volume is 2000 veh/h with 5% trucks. The traffic is commuter
type with peak hour factor 0.92 and interchange density as 0.6 interchanges per kilometer.
Free-way consists of two lanes in each direction of 3.3 m width with lateral clearance of 0.6
m. Find the LOS of free-way during peak hour.
60. At an uncontrolled intersection the cumulative number of gaps accepted and rejected have
been tabulated as shown below. Determine critical gap using Raff's method (illustrate the
result graphically).
Gap (sec) Accepted gaps Rejected gaps
![Page 24: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/24.jpg)
0.0 0 208
0.5 0 208
1.0 0 193
1.5 1 135
2.0 10 84
2.5 26 55
3.0 45 30
![Page 25: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/25.jpg)
3.5 67 15
4.0 86 9
4.5 106 8
5.0 122 4
5.5 140 1
9.5 227 0
61. The entry and exit width of a rotary intersection are 9m and 11m respectively. The width of
approaches at the intersection is 15m. The traffic from the four approaches traversing the
intersection is given below. If the traffic composition is 50% car, 40% two-wheelers and
10% trucks and the passenger car units of two-wheelers and trucks are 0.5 and 3
respectively, find the capacity of the rotary using TRL formulae.
![Page 26: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/26.jpg)
Approach Left turn Straight Right turn
North 500 800 300
South 400 350 450
East 250 400 500
West 300 450 500
62. The entry and exit width of a rotary intersection are 10m each. The width of approaches at
the intersection is 15m. The traffic from the four approaches traversing the intersection is
given below. Find the capacity of the rotary using TRL formulae
Approach Left turn Straight Right turn
North 415 643 350
South 549 358 424
East 408 450 402
![Page 27: Assignment problems Traffic Engineering & Management ... · PDF fileAssignment problems Traffic Engineering & Management (ElectiveII) Solve any three questions [for choosing 3 questions,](https://reader034.vdocument.in/reader034/viewer/2022052213/5a9e43cd7f8b9a6a218ce538/html5/thumbnails/27.jpg)
West 450 423 493
63. A person standing at a stop line of signalized intersection found that the vehicles arrive at
3.7, 6.9, 9.7, 12, 14.1, 16, 17.9, and 19.8 seconds after the start of the green. The signal
turns red at 20th second. Find the lost time, saturation flow and lane capacity. (Assume
cycle is 60 second, amber is 3 s)
64. A person standing at a stop line of signalized intersection found that the vehicles arrive at
3.7, 6.9, 9.7, 12, 14.1, 16, 17.9, and 19.8 seconds after the start of the green. Find the lost
time and saturation headway.
65. Derive an expression for webster's uniform delay and state the assumptions involved..
66. (a) Derive an expression for cycle length calculation for a signalized intersection. (b) Write
briefly on Webster's stopped delay calculations
67. The traffic flow and phase plan for a four-legged intersection is as shown in Figure 8. The
E-W flow is 1420, W-E flow is 1150, N-S flow is 640, and S-N flow is 580 vehicles per
hour. Assume for all the phases the yellow time is 3 seconds, the lost time is 4 seconds,
saturation headway is 1.2 seconds, and degree of saturation is 0.9. Assume left turn
adjustment factor 1.2 and right turn adjustment factor 1.3. Assume the left turn and right
turn traffic proportion of 20% and 30% respectively. If the actual green time allotted for
phase 1,2,3 and 4 is 30,28, 18 and 22 respectively, compute the delay for each lane and total
intersection delay.
68. In the above problem, If the actual green time allotted for phase 1,2,3 and 4 is 30, 35, 8,
and 9 respectively, compute the stopped delay for East-West movement (Assume uniform
vehicle arrival).
69. For the data given in above problem , if the actual green time allocated for phase 1, 2, 3 and
4 is 30, 28, 18 and 22 respectively, calculate the delay for lane 1 and lane 7.
70. Derive pearson type III model and illustrate with numerical example.