According to Indian modular brick practice, what is the standard actual size of a modular brick (excluding mortar thickness)? (Note: Distinguish between actual and nominal dimensions.)
-
A10 × 10 × 9 cm
-
B19 × 9 × 9 cm (actual size)
-
C22.5 × 10 × 8.5 cm
-
D22.5 × 8.0 × 9 cm
Answer
Correct Answer: 19 × 9 × 9 cm (actual size)
Explanation
Introduction:Masonry measurements often distinguish between actual unit size and nominal (including mortar). This question checks recall of the standard actual size of a modular brick used in India.
Given Data / Assumptions:
- Modular brick systems in India specify both actual and nominal sizes.
- Mortar thickness is typically around 10 mm, leading to a larger nominal size.
- The question explicitly asks for actual size.
Concept / Approach:Actual size is the physical brick dimension measured without mortar; nominal size adds the intended mortar joint to simplify layout modularity on site.
Step-by-Step Solution:
1) Recall standard figures: actual = 19 × 9 × 9 cm; nominal ≈ 20 × 10 × 10 cm.2) Compare with given choices and select the exact actual dimensions.3) Confirm that other options do not match Indian modular standards.Verification / Alternative check:Codes and handbooks list 19 × 9 × 9 cm as actual, with 10 mm mortar joints giving nominal 20 × 10 × 10 cm module for coursing and openings.
Why Other Options Are Wrong:
- 10 × 10 × 9 cm: not a recognized standard module.
- 22.5 × 10 × 8.5 cm and 22.5 × 8.0 × 9 cm: resemble non-modular or historical sizes; not the Indian modular actual size.
Common Pitfalls:Confusing actual with nominal; ignoring mortar thickness when setting out openings and lintels; mixing regional sizes.
Final Answer:19 × 9 × 9 cm (actual size)