Following table specifies requirements of M-20 concrete mix design as per IS-10262-2009 and MORT&H (Ministry of Road Transport and Highways.)
|
M-20 CONCRETE MIX DESIGN |
||
|
As per IS 10262-2009 & MORT&H |
||
|
A-1 |
Stipulations for Proportioning | |
|
1 |
Grade Designation | M20 |
|
2 |
Type of Cement | OPC 53 grade confirming to IS-12269-1987 |
|
3 |
Maximum Nominal Aggregate Size | 20 mm |
|
4 |
Minimum Cement Content (MORT&H 1700-3 A) | 250 kg/m3 |
|
5 |
Maximum Water Cement Ratio (MORT&H 1700-3 A) | 0.5 |
|
6 |
Workability (MORT&H 1700-4) | 25 mm (Slump) |
|
7 |
Exposure Condition | Normal |
|
8 |
Degree of Supervision | Good |
|
9 |
Type of Aggregate | Crushed Angular Aggregate |
|
10 |
Maximum Cement Content (MORT&H Cl. 1703.2) | 540 kg/m3 |
|
11 |
Chemical Admixture Type | Superplasticiser Confirming to IS-9103 |
|
A-2 |
Test Data for Materials | |
|
1 |
Cement Used | Coromandal King OPC 53 grade |
|
2 |
Sp. Gravity of Cement | 3.15 |
|
3 |
Sp. Gravity of Water | 1.00 |
|
4 |
Chemical Admixture | Not Used |
|
5 |
Sp. Gravity of 20 mm Aggregate | 2.884 |
|
6 |
Sp. Gravity of 10 mm Aggregate | 2.878 |
|
7 |
Sp. Gravity of Sand | 2.605 |
|
8 |
Water Absorption of 20 mm Aggregate | 0.97% |
|
9 |
Water Absorption of 10 mm Aggregate | 0.83% |
|
10 |
Water Absorption of Sand | 1.23% |
|
11 |
Free (Surface) Moisture of 20 mm Aggregate | nil |
|
12 |
Free (Surface) Moisture of 10 mm Aggregate | nil |
|
13 |
Free (Surface) Moisture of Sand | nil |
|
14 |
Sieve Analysis of Individual Coarse Aggregates | Separate Analysis Done |
|
15 |
Sieve Analysis of Combined Coarse Aggregates | Separate Analysis Done |
|
15 |
Sp. Gravity of Combined Coarse Aggregates | 2.882 |
|
16 |
Sieve Analysis of Fine Aggregates | Separate Analysis Done |
|
A-3 |
Target Strength for Mix Proportioning | |
|
1 |
Target Mean Strength (MORT&H 1700-5) | 30N/mm2 |
|
2 |
Characteristic Strength @ 28 days | 20N/mm2 |
|
A-4 |
Selection of Water Cement Ratio | |
|
1 |
Maximum Water Cement Ratio (MORT&H 1700-3 A) | 0.5 |
|
2 |
Adopted Water Cement Ratio | 0.5 |
|
A-5 |
Selection of Water Content | |
|
1 |
Maximum Water content (10262-table-2) | 186 Lit. |
|
2 |
Estimated Water content for 25 mm Slump | 145 Lit. |
|
3 |
Superplasticiser used | nil |
|
A-6 |
Calculation of Cement Content | |
|
1 |
Water Cement Ratio | 0.5 |
|
2 |
Cement Content (145/0.5) | 290 kg/m3 |
| Which is greater then 250 kg/m3 | ||
|
A-7 |
Proportion of Volume of Coarse Aggregate & Fine Aggregate Content | |
|
1 |
Vol. of C.A. as per table 3 of IS 10262 | 62.00% |
|
2 |
Adopted Vol. of Coarse Aggregate | 65.00% |
| Adopted Vol. of Fine Aggregate ( 1-0.65) | 35.00% | |
|
A-8 |
Mix Calculations | |
|
1 |
Volume of Concrete in m3 | 1.00 |
|
2 |
Volume of Cement in m3 | 0.09 |
| (Mass of Cement) / (Sp. Gravity of Cement)x1000 | ||
|
3 |
Volume of Water in m3 | 0.145 |
| (Mass of Water) / (Sp. Gravity of Water)x1000 | ||
|
4 |
Volume of Admixture @ 0% in m3 | nil |
| (Mass of Admixture)/(Sp. Gravity of Admixture)x1000 | ||
|
5 |
Volume of All in Aggregate in m3 | 0.763 |
| Sr. no. 1 – (Sr. no. 2+3+4) | ||
|
6 |
Volume of Coarse Aggregate in m3 | 0.496 |
| Sr. no. 5 x 0.65 | ||
|
7 |
Volume of Fine Aggregate in m3 | 0.267 |
| Sr. no. 5 x 0.35 | ||
|
A-9 |
Mix Proportions for One Cum of Concrete (SSD Condition) | |
|
1 |
Mass of Cement in kg/m3 | 290 |
|
2 |
Mass of Water in kg/m3 | 145 |
|
3 |
Mass of Fine Aggregate in kg/m3 | 696 |
|
4 |
Mass of Coarse Aggregate in kg/m3 | 1429 |
| Mass of 20 mm in kg/m3 | 1029 | |
| Mass of 10 mm in kg/m3 | 400 | |
|
5 |
Mass of Admixture in kg/m3 | nil |
|
6 |
Water Cement Ratio | 0.5 |