Question

Which of the following statements is/are correct with respect to temporary structures during construction?

• A. Centering supports formwork for arches, domes, and slabs.
• B. Scaffolding provides working platforms for masons.
• C. Shoring helps in preventing dampness in buildings.
• D. Underpinning strengthens or deepens foundations.

Hint:

Dampness in a building is stopped by damp-proof courses and membranes, not by any temporary support structure like shoring.

Answer 1

The Correct Option is A, B, D

Step 1: Understanding the Question:
We are given four statements about temporary structures used during building construction, and we must find which ones are correct.

Step 2: Checking statement (A):
Centering is the temporary timber or steel support built to hold the formwork of curved and spanning structural elements, such as arches, domes, and slabs, in their correct shape until the concrete or masonry gains enough strength to carry itself. This matches the statement, so (A) is correct.

Step 3: Checking statement (B):
Scaffolding is the temporary framework of tubes, couplers, and planks put up alongside a building under construction to give masons, plasterers, and other workers a safe working platform at height and to hold their tools and materials. This matches the statement exactly, so (B) is correct.

Step 4: Checking statement (C):
Shoring is a temporary support given to an existing wall, floor, or structure to hold it up safely during construction, alteration, demolition of a nearby structure, or repair, stopping collapse from a loss of lateral or vertical support. It plays no part in keeping moisture out of a building; damp proofing is handled separately with damp-proof courses, membranes, and coatings. So the claim that shoring helps in preventing dampness is incorrect, making (C) wrong.

Step 5: Checking statement (D):
Underpinning is the technique of extending a foundation in depth or in bearing area, usually by working in short sections beneath the existing footing, to raise its load capacity or take it down to firmer soil. This matches strengthens or deepens foundations exactly, so (D) is correct.

Step 6: Final Answer:
Statements (A), (B), and (D) are correct, while (C) wrongly credits shoring with preventing dampness.
\[ \boxed{\text{Options (A), (B), (D)}} \]