| Requirement of cement, water , dry aggregate(both coarse and fine) for different grades ofconcrete(Nominal Mix) work are given as under: |
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Table 9 Proportions for Nominal Mix Concrete
(Clauses 9.3 and 9.3.1)
IS 456-2000
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| Grade |
Nominal mixusually
adopted |
Consumption of
cement(bags) per
cum of concrete |
Quantity of water
per 50kg.of
cement mix(litres) |
*Total Quantity of
Dry aggregate by
Mass per 50 kg of
cement, kg(max) |
| M 20 |
1:1.5:3 |
8.00 |
30 |
250 |
| M 15 |
1:2:4 |
6.40 |
32 |
330 |
| M 10 |
1:3:6 |
4.40 |
34 |
480 |
| M 7.5 |
1:4:8 |
3.40 |
45 |
625 |
| M 5 |
1:6:12 |
2.20 |
60 |
800 |
|
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| *Total quantity= Sum of the individual masses of fine and coarse aggregates, kg |
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| Proportion of fine aggregate to coarse aggregate (by mass) : Generally 1:2 but subject to an upper limit of 1:1.5 and a lower limit of 1:2.5 |
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| Note: The proportion of fine aggregate to coarse aggregate should be adjusted from upper limit to lower limit progressively as the grading of fine aggregate becomes finer and the maximum size of the coarse aggregate becomes larger. Graded coarse aggregate shall be used. |
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| Example: For an average grading of fine aggregate(That is Zone II of Table 4 of IS 383) the proportions shall be 1:1.5, 1:2, 1:2.5 for maximum size of aggregates 10mm, 20mm and 40mm respectively |
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