Highway planning miscellaneous
- The penetration value of bitumen sample tested at 25°C is 80. When this sample is heated to 60°C and tested again, the needle of the penetration test apparatus penetrates the bitumen sample by d mm. The value of d CANNOT be less than _____ mm.
-
View Hint View Answer Discuss in Forum
8
Correct Option: D
8
- The probability that k number of vehicles arrive (i.e. cross a predefined line) in time t is given as (λt)ke-λt/k! where λ is the average vehicle arrival rate. What is the probability that the time headway is greater than or equal to time t1 ?
-
View Hint View Answer Discuss in Forum
Probability of k vehicles arrival,
P(k) = (λt)ke-λt1 k!
Time headway ≥ t1 means no vehicle arrives i.e., k = 0
∴ P(k) = e-λt1Correct Option: D
Probability of k vehicles arrival,
P(k) = (λt)ke-λt1 k!
Time headway ≥ t1 means no vehicle arrives i.e., k = 0
∴ P(k) = e-λt1
- A vehicle negotiates a transition curve with uniform speed v. If the radiuses of the horizontal curve and the allowable jerk are R and J, respectively, the minimum length of the transition curve is
-
View Hint View Answer Discuss in Forum
L = v³ JR
Jerk, J is the rate of change of acceleration.Correct Option: D
L = v³ JR
Jerk, J is the rate of change of acceleration.
- If v is the initial speed of a vehicle, g is the gravitational acceleration, G is the upward longitudinal slope of the road and ƒ>sub>r is the coefficient of rolling friction during braking, the braking distance (measured horizontally) for the vehicle to stop is
-
View Hint View Answer Discuss in Forum
L = v² 2g (ƒ + G) Correct Option: B
L = v² 2g (ƒ + G)
- 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 the following data:
Design life = 15 years
Commercial vehicle count before pavement construction = 4500 vehicles/day
Annual traffic growth rate = 8%.
The vehicle damage factor used in the calculation was
-
View Hint View Answer Discuss in Forum
msa = 365A[(1 + r)h] × F r 100 × 106 = 365 × 4500 1 + 8 15 - 1 100 8 100
∴ F = 2.24Correct Option: B
msa = 365A[(1 + r)h] × F r 100 × 106 = 365 × 4500 1 + 8 15 - 1 100 8 100
∴ F = 2.24