Difficulty: Easy
Correct Answer: All the above.
Explanation:
Introduction / Context:
Earthwork measurement varies with site conditions. Surveyors select techniques that best reflect actual excavation or filling. Understanding when to use average depths (dead men), level differences, or filling-based back-calculation ensures fair and auditable quantities.
Given Data / Assumptions:
Concept / Approach:
In uniform ground, average depths from fixed reference points give reliable volumes. In irregular ground, pre- and post-work levels yield volumetric differences. Where neither works (e.g., access constraints, waterlogged conditions), back-calculate from filled quantities and deduct voids to approximate the in-situ earthwork.
Step-by-Step Solution:
Confirm A: Average depth method with dead men is standard for uniform ground.Confirm B: Level-difference (strip levels or grid) is appropriate for irregular ground.Confirm C: When direct measurement is infeasible, using fill with voids deduction is accepted practice.Hence D (All the above) is correct.
Verification / Alternative check:
Field manuals outline all three as valid, with documentation of assumptions (e.g., bulking/void ratios) when using filling-based estimates.
Why Other Options Are Wrong:
Common Pitfalls:
Ignoring bulking/compaction factors; using the average-depth method in highly irregular ground.
Final Answer:
All the above.
Discussion & Comments