03/01/2026
Practical Civil Engineering Interview Questions, Part 48 – Transportation Engineering (Road & Highway Engineering – Practical & Technical)
1. What is transportation engineering?
A branch of civil engineering concerned with the planning, design, construction, operation, and maintenance of transportation systems.
2. What are the main components of highway engineering?
Geometric design, pavement design, traffic engineering, drainage, and maintenance.
3. What factors govern highway alignment selection?
Traffic demand, topography, soil conditions, environmental impact, cost, and safety.
4. What is highway geometric design?
The design of visible road features such as alignment, curves, gradients, cross-section, and sight distance.
5. What is design speed and why is it important?
The selected speed used to determine geometric features to ensure safety and comfort.
6. What is camber in road construction?
The transverse slope provided to drain rainwater from the road surface.
7. What are common camber values for highways?
Bituminous roads: 2–3%
Concrete roads: 1.5–2%
8. What is right of way (ROW)?
The total width of land acquired for highway construction and future expansion.
9. What is a traffic survey?
Systematic data collection on traffic volume, speed, axle load, and composition.
10. What are the common types of traffic surveys?
Traffic volume, speed study, origin–destination study, and axle load survey.
11. What is PCU in traffic engineering?
Passenger Car Unit used to convert different vehicle types into equivalent cars.
12. What is pavement design?
The process of determining pavement thickness and layer composition to withstand traffic loads.
13. What are the types of pavements?
Flexible pavement, rigid pavement, and composite pavement.
14. What is ESAL in pavement design?
Equivalent Single Axle Load used to quantify traffic loading over pavement life.
15. What is the role of drainage in highways?
To prevent water accumulation that weakens pavement and subgrade.
16. What is shoulder in a highway?
An adjacent strip provided for vehicle safety, emergency stopping, and pavement support.
17. What is a median in road design?
A central strip separating opposing traffic flows to improve safety.
18. What causes highway pavement failures?
Poor drainage, inadequate compaction, overloading, weak subgrade, and aging.
19. What maintenance activities are essential for highways?
Pothole repair, crack sealing, resurfacing, drainage cleaning, and shoulder repair.
20. What documents are maintained for highway projects?
Design drawings, traffic data, material test reports, QC records, and as-built drawings.
Hussaini Muhammad Sulaiman, GMNSE
New Horizons Limited
Multi-Disciplinary Engineering Services
