Steel sleepers – principal disadvantages Which of the following best summarizes the main disadvantages of steel sleepers used on railway track?

Introduction / Context:
Steel sleepers were widely used due to their strength and uniformity. However, they come with specific drawbacks that influence maintenance and life-cycle costs. This question assesses awareness of those disadvantages.

Given Data / Assumptions:

• Disadvantages listed include corrosion and lug failures.
• We consider typical ballasted track conditions in Indian climates.

Concept / Approach:
Steel is susceptible to corrosion, especially in humid, coastal, or aggressive environments. Mechanical features like lugs (used for holding fastenings) can be damage-prone under repeated load and maintenance operations.

Step-by-Step Solution:
Evaluate corrosion: legitimate concern → steel sleepers need coatings/painting and still corrode over time.Evaluate lugs: repeated stress, tamping, and fastening works can cause breakage or splitting.All listed issues are recognized in practice → choose 'All the above'.

Verification / Alternative check:
Maintenance manuals note corrosion mitigation requirements for steel sleepers and document lug damage incidents, validating these drawbacks.

Why Other Options Are Wrong:
Any single item does not capture the composite disadvantage profile found in field practice.

Common Pitfalls:
Assuming that protective coatings eliminate rust risk entirely; in reality, coatings reduce but do not eliminate corrosion, especially where maintenance damages the protective layer.

Final Answer:
All the above