Transportation Engineering Questions and Answers Part-9

1. In how many categories are motor vehicles classified by AASHTO?
a) 4
b) 5
c) 3
d) 1

Answer: a
Explanation: Motor vehicles are classified by AASHTO into four main categories and they are Passenger cars (SUVs, minivans, pickup trucks), Buses (transit buses, school buses), Trucks (single unit trucks, tractor-trailer, tractor semi-trailer combination vehicles) and Recreational vehicles (cars with various types of trailers).

2. Which of the following is critical vehicle property for the design of roadways and traffic control?
a) Type of engine
b) Type of fuel the vehicle runs on
c) Acceleration
d) Age of vehicle

Answer: c
Explanation: Acceleration is one of the critical vehicle property for the design of roadways and traffic con-trol. Braking and deceleration, low speed and high speed turning characteristics are also some of the criti-cal vehicle property required for the design of roadways and traffic control.

3. How many design vehicles has AASHTO specified for geometric design of road?
a) 10
b) 11
c) 13
d) 20

Answer: d
Explanation: AASHTO has specified 20 design vehicles, each with specified characteristics for geometric design of the road. Some of the design vehicles as specified by AASHTO are P for passenger cars, SU for single truck unit, BUS-40 for intercity bus with 40ft wheelbase.

4. Which of the following is the incorrect use of Design vehicles?
a) Design of turning roadways
b) Design of intersection curbs
c) Determination of lane widths
d) Design of different types of vehicles

Answer: d
Explanation: Design vehicles are used for the design of turning roadways and intersection curbs primarily. It is also used to determine lane widths such as lane widening on curves.

5. Which of the following is the minimum design vehicle for local street applications?
a) Passenger car
b) Single-unit truck
c) Intercity bus
d) Triple semi-trailer

Answer: b
Explanation: The minimum design vehicle for local street applications is Single-unit truck because hook and ladder fire vehicles have rear axle steering that allows the vehicle to negotiate sharp turns, so the use of the single unit truck is not considered to hinder emergency vehicle.

6. Which of the following is the design vehicle for parking lots?
a) Passenger car
b) Single-unit truck
c) Intercity bus
d) Triple semi-trailer

Answer: a
Explanation: The design vehicle generally used for parking lots is Passenger car (P). Access to emergency vehicles is also considered in the design of parking lots in all the buildings and public places.

7. For the design of highways and intersections, the selection of design vehicle must consider __________
a) Vehicle length
b) Vehicle mix
c) Emergency vehicles
d) Topography

Answer: b
Explanation: For the design of highways and intersections, the selection of design vehicle must consider the expected vehicle mix. The design vehicle should accommodate 95% or more of the expected vehicle mix.

8. What is the height range of design vehicles?
a) 4.25 ft—13.5 ft
b) 4.5 ft—13.5 ft
c) 4.25 ft—14 ft
d) 4.25 ft—15 ft

Answer: a
Explanation: The height range of design vehicles is 4.25 ft for passenger vehicles and 13.5 ft for large trucks. According to this range, design of roadways is accomplished.

9. What is the minimum clearance for most facilities?
a) 13 ft
b) 15 ft
c) 10 ft
d) 14 ft

Answer: d
Explanation: The minimum clearance for most facilities is 14 ft. This is so because all facilities must ac-commodate emergency vehicles.

10. What is the width range of design vehicles?
a) 7 ft — 8.5 ft
b) 5 ft — 10 ft
c) 2 ft — 8 ft
d) 4 ft — 10 ft

Answer: a
Explanation: The width range of design vehicles is 7 ft for passenger vehicles and 8.5 ft for large trucks. This data influences the design of lane width and shoulders.