In method-of-measurement terminology, excavation exceeding 1.5 m in width and 10 sq.m in plan area but with a depth not exceeding 30 cm is termed as which type of item?
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AExcavation
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BSurface dressing
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CCutting
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DSurface excavation
Answer
Correct Answer: Surface excavation
Explanation
Introduction / Context:Different excavation items are distinguished by width, area, and depth because equipment, productivity, and disposal differ. Recognizing the correct classification ensures the correct rate basis and prevents disputes.
Given Data / Assumptions:
- Width > 1.5 m and plan area > 10 sq.m.
- Depth ≤ 0.30 m.
- Open excavation near the surface.
Concept / Approach:Shallow removals over larger areas are classified as 'surface excavation'. In contrast, 'surface dressing' typically refers to light trimming or removing vegetation/topsoil to a very shallow depth (often up to 15 cm). Deeper or narrower cuts fall under general excavation or trenching items.
Step-by-Step Solution:1) Check thresholds: depth ≤ 0.30 m → qualifies as shallow.2) Area and width exceed minimums → it is not a trench or isolated pit.3) Hence, classify the item as 'surface excavation'.
Verification / Alternative check:Schedules of Rates and IS measurement guidelines enumerate 'surface excavation' with limits closely matching the given thresholds.
Why Other Options Are Wrong:
- Excavation/Cutting: Generic terms but typically used for deeper removals.
- Surface dressing: Shallower and lighter operation than specified here.
Common Pitfalls:
- Confusing topsoil stripping (surface dressing) with surface excavation.
- Misclassifying trenches as surface excavation when width ≤ 1.5 m.
Final Answer:Surface excavation.