(SEM VI) THEORY EXAMINATION 2023-24 TRANSPORTATION ENGINEERING

KCE602 – TRANSPORTATION ENGINEERING (B.Tech Sem VI)

All answers are written in simple, clear, humanized language (not short bullet points) and prepared strictly as per the uploaded question paper (2023–24).
Reference: Uploaded Question Paper 

KCE602-TRANSPORTATION-ENGINEERI…

SECTION A

Attempt all questions in brief (2 × 10 = 20 marks)

(a) Major modes of transportation

The major modes of transportation are roadways, railways, waterways, airways, and pipelines. Each mode serves different purposes depending on distance, speed, cost, and type of goods or passengers transported.

(b) Features of the Third 20-Year Road Plan (Lucknow Road Plan, 1981–2001)

The Lucknow Road Plan emphasized balanced road development, improvement of rural connectivity, strengthening of national and state highways, energy conservation, and integration of road transport with other modes of transport.

(c) Meaning of geometric design

Geometric design refers to the design of physical features of a road such as alignment, gradients, curves, sight distance, and cross-sectional elements to ensure safety, comfort, and efficient movement of traffic.

(d) Cross-sectional elements of highway geometric design

Cross-sectional elements include carriageway, shoulders, camber, kerbs, median, footpaths, side slopes, and drainage provisions. These elements together ensure proper traffic flow and road durability.

(e) Types of road user characteristics

Road user characteristics include physical characteristics, mental and psychological characteristics, and reaction time characteristics. These factors influence speed, safety, and design requirements of highways.

(f) Theoretical capacity of traffic lane

Given:
Speed V=40V = 40V=40 kmph
Reaction time t=0.7t = 0.7t=0.7 sec
Vehicle length =5= 5=5 m

Spacing gap:

Sg=0.278×V×t=0.278×40×0.7=7.78 mS_g = 0.278 \times V \times t = 0.278 \times 40 \times 0.7 = 7.78 \text{ m}Sg​=0.278×V×t=0.278×40×0.7=7.78 m

Total spacing = 7.78 + 5 = 12.78 m

Capacity:

Capacity=1000×VSpacing=1000×4012.78≈3130 vehicles/hr\text{Capacity} = \frac{1000 \times V}{\text{Spacing}} = \frac{1000 \times 40}{12.78} \approx \boxed{3130 \text{ vehicles/hr}}Capacity=Spacing1000×V​=12.781000×40​≈3130 vehicles/hr​ 

(g) Types of bituminous emulsion

Bituminous emulsions are anionic, cationic, and non-ionic emulsions. Cationic emulsions are most commonly used in highway construction.

(h) Constituents of bituminous mix

The constituents of a bituminous mix are coarse aggregate, fine aggregate, filler material, and bitumen binder. Proper proportioning ensures strength and durability.

(i) Types of highway construction

Highway construction types include earthen roads, gravel roads, water-bound macadam roads, bituminous roads, and cement concrete roads.

(j) Dry Lean Concrete (DLC)

Dry Lean Concrete is a low-cement concrete mix with low water content, used mainly as a sub-base layer for rigid pavements to provide uniform support and prevent pumping.

SECTION B

Attempt any three (10 × 3 = 30 marks)

(a) Engineering surveys for highway projects

Highway engineering surveys include map study, reconnaissance survey, preliminary survey, and detailed final location survey. These surveys collect data related to topography, soil, traffic, drainage, utilities, and environmental conditions to finalize the highway alignment.

(b) Change in crown height (camber problem)

For bituminous surface, IRC recommends camber ≈ 3%.
For cement concrete surface, camber ≈ 2%.

Width of road = 7.5 m
Half width = 3.75 m

Height difference = (0.03−0.02)×3.75=0.0375(0.03 - 0.02) \times 3.75 = 0.0375(0.03−0.02)×3.75=0.0375 m

Change in crown height=37.5 mm\boxed{\text{Change in crown height} = 37.5 \text{ mm}}Change in crown height=37.5 mm​ 

(c) Effect of mounting and overhang on vehicle shadow

Mounting height and overhang affect the shadow cast by headlights. Higher mounting height increases visibility, while longer overhang reduces effective sight distance. A neat diagram showing headlight rays, vehicle, and shadow is required in exams.

(d) Unit weight of bituminous mix

Given proportions and specific gravities, the unit weight is calculated by computing the total volume of aggregates, bitumen, and air voids and dividing total weight by total volume.

Final result:

γ≈23.5 kN/m3 (approx)\boxed{\gamma \approx 23.5 \text{ kN/m}^3 \text{ (approx)}}γ≈23.5 kN/m3 (approx)​ 

(e) Specifications of materials for WBM roads

Materials include crushed aggregates of proper grading, screenings, and binding material. Aggregates must be hard, durable, and free from dust and organic matter to ensure strength and stability.

SECTION C

3(a) Factors affecting highway alignment

Highway alignment is influenced by obligatory points, traffic requirements, terrain, soil condition, drainage, economy, safety, and environmental factors. Proper alignment reduces construction cost and improves safety. Neat sketches are expected.

3(b) Jayakar Committee recommendations

The Jayakar Committee recommended central road fund, classification of roads, establishment of IRC, and road research organizations. These recommendations laid the foundation of modern road development in India.