Flat slab terminology: In a flat slab system, the enlarged head provided at the top of a supporting column (to reduce punching shear and improve load transfer) is technically called the ________.
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ASupporting end of the column
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BTop of the column
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CCapital
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DDrop panel
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ENone of these
Answer
Correct Answer: Capital
Explanation
Introduction / Context:Flat slabs transfer load directly to columns without beams. To control punching shear and improve load distribution, two local thickenings are used: the column capital (enlarged head on the column) and the drop panel (thickened slab around the column).
Given Data / Assumptions:
- Question asks the name of the enlarged column head in a flat slab.
- No calculation is required.
Concept / Approach:The column capital is the flared or enlarged portion at the top of a column. It reduces the intensity of shear at the slab–column junction and increases the perimeter available to resist punching. A drop panel, in contrast, is the local thickening of the slab itself around the column.
Step-by-Step Solution:Identify which element belongs to the column (capital) versus the slab (drop).Match the definition: “enlarged head at the top of a supporting column” → capital.Select option (c).
Verification / Alternative check:Standard flat slab details in textbooks show both capital and drop panel; the capital is unmistakably part of the column.
Why Other Options Are Wrong:
- (a) and (b) are generic phrases; they do not denote the technical element.
- (d) Drop panel is a thickening of the slab, not the column head.
- (e) Not applicable.
Common Pitfalls:Confusing capital and drop panel because both increase punching shear capacity; remembering that capital belongs to column, drop belongs to slab helps.
Final Answer:Capital