M10 grade of concrete approximates ……… nominal mix.
Correct Answer: A. 1:3:6
📚 Detailed Explanation: M10 = 1:3:6 Nominal Mix
Why A (1:3:6) is correct: M10 is the lowest standard concrete grade specified in IS 456. The nominal mix 1:3:6 (1 part cement : 3 parts sand : 6 parts coarse aggregate by volume) produces concrete with a 28-day characteristic compressive strength of approximately 10 N/mm². The high aggregate-to-cement ratio makes this a lean, economical mix suitable for non-structural applications.
Nominal Mix Grade Chart
| Grade | Nominal Mix (C:FA:CA) | fck | Category |
|---|---|---|---|
| M10 | 1:3:6 | 10 N/mm² | Ordinary |
| M15 | 1:2:4 | 15 N/mm² | Ordinary |
| M20 | 1:1.5:3 | 20 N/mm² | Standard |
| M25 | 1:1:2 | 25 N/mm² | Standard |
- M10 ≈ 1:3:6 mix (leanest standard nominal mix).
- Used for blinding/levelling layers, non-structural plain concrete, and temporary works.