Transportation Engineering
Exam Duration: 45 Mins Total Questions : 30
At a horizontal curve portion of a four lane undivided carriageway, a transition curve is to be introduced to attain required super-elevation.The design speed is 60 km/h and the radius of curve is 245m. Assume length of wheel base of a longest vehicle as 6m, super-elevation rate as 5% and rate of introduction of this super-elevation as 1 in 150.The length of transition curve(m) required, if the pavement is rotated about the inner edge is
- (a)
81.4
- (b)
85.0
- (c)
91.5
- (d)
110.2
While designing a hill road with a ruling gradient of 6%, if a sharp horizontal curve of 50 m radius is encountered, the compensated gradient at the curve as per IRC specifications should be
- (a)
4.4%
- (b)
4.75%
- (c)
5.0%
- (d)
5.25%
If due to some practical reasons, there is no friction, then this will results in the situation where
- (a)
the pressure on the outer wheel is zero
- (b)
the pressure on the outer wheel is less than that of inner wheel.
- (c)
the pressure on the outer wheel is equal to that of inner wheel
- (d)
the pressure on the outer wheel is more than that of inner wheel
The psychological widening as per IRC guidelines varies with
- (a)
\(\frac { { v }^{ 2 } }{ \sqrt { R } } \)
- (b)
\(\frac { { v }^{ 2 } }{ R } \)
- (c)
\(\frac { v }{ R } \)
- (d)
\(\frac { v }{ \sqrt { R } } \)
A vehicle travels the transition curve of radius 150 m in duration 15 s at a design speed of 80 km/h.The rate of change of centrifugal acceleration is
- (a)
0.62 m/s3
- (b)
0.49 m/s3
- (c)
0.22 m/s3
- (d)
0.17 m/s3
The maximum superelevation to be provided on a road curve is 1 in 15.If the rate of change of super-elevation is specified as 1 in 120 and the road width is 10 m, then the minimum length of the transition curve on either end will be
- (a)
180 m
- (b)
125 m
- (c)
80 m
- (d)
30 m
A horizontal curve of 480 m radius for 7.5 m two lane road is to be designed for a speed of 80 km/h.The raising of the outer edge of pavement with respect to the centre line to cater the mixed traffic condition is
- (a)
0.14 m
- (b)
0.22 m
- (c)
0.24 m
- (d)
0.44 m
If an ascending gradient of 1 in 40 meets with a descending gradient of 1 in 40, the length of Summit curve for a stopping sight distance of 70 m will be
- (a)
85 m
- (b)
72 m
- (c)
56 m
- (d)
47 m
In a bituminous concrete mix bitumen and aggregates by weight are 10% and 90%, respectively. The specific gravity of bitumen and aggregates are 1.02 and 2.72 respectively. Theoretical unit weight the mix will be
- (a)
1.79 g/cm3
- (b)
2.12 g/cm3
- (c)
2.33 g/cm3
- (d)
2.43 g/cm3
Using, IRC 37-1984 guidelines for the design of flexible pavements and the following data, choose the total thickness of the pavement.
Number of commercial vehicles when construction is completed=\(2723\frac { vehicles }{ day } \)
Annual growth rate of the traffic=5.0%
Design life of the pavement=10 yr
Vehicle damage factor=2.4
CBR value of subgrade soil=5%
Data for 5% CBR value
| No.of standard axie(msa) | Total thickness(mm) |
|---|---|
| 20 | 620 |
| 25 | 640 |
| 30 | 670 |
| 40 | 700 |
- (a)
620 mm
- (b)
640 mm
- (c)
670 mm
- (d)
700 mm
What is the spacing between contraction joints for 4.0 m slab width having a thickness of 20 cm and f=1.5 for the RCC pavement having 1.0 cm bar dia at 0.30 in spacing?
- (a)
8.32 m
- (b)
9.68 m
- (c)
10.18 m
- (d)
11.32 m
The following data pertains to the number of commercial vehicles per day for the design of flexible pavement for a national highway as per IRC 37.1984
| Type of commercial vehicle | No. of vehicles per day | Vehicle damage factor |
|---|---|---|
| Two-axie trucks | 2000 | 5 |
| Tandem-axie trucks | 200 | 6 |
Assuming a traffic growth factor of 7.5% per annum for both types of vehicles.The cumulative number of standard axie load repetition for a design life of 10 yr is
- (a)
44.6
- (b)
57.8
- (c)
62.4
- (d)
78.7
If the radius of wheel load distribution is 30 cm and the slab thickness is 15 cm, then the equivalent radius of resisting section is
- (a)
29.56 cm
- (b)
39.68 cm
- (c)
30 cm
- (d)
15 cm
If average distance headway is 25 m, then the basic capacity of a traffic lane at speed of 72 km/h is
- (a)
2820 vehicles/h
- (b)
2500 vehicles/h
- (c)
1500 vehicles/h
- (d)
1000 vehicles/h
If normal flows on two approach roads at an intersection are respectively 500 PCU per hour and 300 PCU/h, the saturation flows are 1600 PCU/h on each road and the total lost time per signal is 16 s, then optimum cycle length time per Webster's method is
- (a)
72.5 s
- (b)
58 s
- (c)
48 s
- (d)
19.3 s
The probability that K-number of vehicles arrive i.e., in time t is given as \(\frac { { \left( \lambda t \right) }^{ k }{ e }^{ -\lambda t } }{ K! } \) where \(\lambda \) is the average vehicle arrival rate.What is the probability that the time head way is greater than or equal to time t1 ?
- (a)
\(\lambda { e }^{ \lambda { t }_{ 1 } }\)
- (b)
\(\lambda { e }^{ { -t }_{ 1 } }\)
- (c)
\({ e }^{ \lambda { t }_{ 1 } }\)
- (d)
\({ e }^{ -\lambda { t }_{ 1 } }\)
If aggregate size of 40-50 mm is to be tested for finding out the portion of elongated aggregate using length gauge, the slot length of the gauge should be
- (a)
81 mm
- (b)
45 mm
- (c)
53 mm
- (d)
90 mm
The length of summit curve on a two lane two way highway depends upon
- (a)
allowable rate of change of centrifugal acceleration
- (b)
the coefficient of lateral friction
- (c)
required stopping sight distance
- (d)
required overtaking sight distance
A pavement designer has arrived at a design traffic of 100 million standard axles for a newly developing national highway as per IRC:37 guidelines using following data: design life=15 yr, commercial vehicle count before pavement construction=4500 vehicles/day, annual traffic growth rate=8%.The vehicle damage factor used in the calculation was
- (a)
1.53
- (b)
2.24
- (c)
3.66
- (d)
4.14
A linear relationship observed between speed and density on a ,certain section of a highway. The free flow speed is observed to be 80 km/h and the jam density is estimated as 100 vehicles/km length. The maximum flow expected on this section and the speed at the maximum flow will respectively be
- (a)
8000 vehicles/h and 80 km/h
- (b)
8000 vehicles/h and 25 km/h
- (c)
2000 vehicles/h and 80 km/h
- (d)
2000 vehicles/h and 40 km/h
If due to some practical reasons, there is no friction, then this will results in the situation where
- (a)
the pressure on the outer wheel is zero.
- (b)
the pressure on the outer wheel is less than that of inner wheel.
- (c)
the pressure on the outer wheel is equal to that of inner wheel.
- (d)
the pressure on the outer wheel is more than that of inner wheel
A traffic stream in a particular direction of a two lane road is moving with a constant speed of 50 km/h, with an average headway of 2.52 s. The longitudinal distance between two consecutive vehicles is
- (a)
30 m
- (b)
35 m
- (c)
38 m
- (d)
42 m
On an urban road, the free mean speed was measured as 70 km/h and average spacing between the vehicles under Jam condition as 7.0 m. The speed flow-density equation is given by
u = usf \(\left[ 1-\frac { K }{ { K }_{ J } } \right] \) and q = uK
The maximum flow (vehicles/h) per lane for this condition is equal to
- (a)
2000
- (b)
2500
- (c)
3000
- (d)
3500
A subgrade soil sample was tested using standard CBR apparatus and the observations are given below
| Load (kg) | Penetration (mm) |
| 60.5 | 2.5 |
| 80.5 | 5.0 |
The CBR value (%) of the sample is
- (a)
6.5
- (b)
5.5
- (c)
4.4
- (d)
3.9
A transport company operates a scheduled daily truck service between city P and Q. One-way Journey time between these two cities is 85 h. A minimum longer time of 5 h is provided at each city. How many truck are required to provide this service
- (a)
4
- (b)
6
- (c)
7
- (d)
8
The following observations were made of an axle load survey on a road.
| Axle load (kN) | Repetitions per day |
| 35-45 | 800 |
| 75-85 | 400 |
The standard axle load is 80 kN. Equivalent daily number of repititions for the standard axle load are
- (a)
450
- (b)
480
- (c)
800
- (d)
1200
For a road with camber of 3% and the design speed of 80 km/h. The minimum radius of the curve beyond which no super elevation is needed is
- (a)
1680 m
- (b)
948 m
- (c)
406 m
- (d)
280 m
The data given below portion to the design of a flexible pavement. Initial traffic = 1213 cv/d
Traffic growth = 8% per annum
Design life = 12 yr
Vehicle damage factor = 2.5
Distribution factor = 1.0
The design traffic in terms of million standard axle (msa) would be
- (a)
0.06 msa
- (b)
8.40 msa
- (c)
21.00 msa
- (d)
32.26 msa
If super-elevation is not provided on a horizontal curve of a highway, then on which portion of the road curve pot holes likely to develop ?
- (a)
Outer edge of road
- (b)
Inner edge of road
- (c)
Centre of road
- (d)
Shoulder of road
For 20 cm thick cement concrete pavement, analysis of stresses gives the following values
Wheel load stress due to corner loading = 30 kg/cm2
Wheel load stress due to edge loading = 35 kg/cm2
Warping stress at corner region due to summer = 10 kg/cm2
Warping stress at corner region due to winter = 8 kg/cm2
Warping stress at edge region due to summer = 9 kg/cm2
Warping stress at corner region due to winter = 6 kg/cm2
Frictional stress during summer = 5 kg/cm2
Frictional stress during winter = 4 kg/cm2
(i) The most critical value of stress for this pavement during summer is
- (a)
40 kg/cm2
- (b)
35 kg/cm2
- (c)
39 kg/cm2
- (d)
44 kg/cm2
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