Project on Concrete Mix Design for various grades of Concrete

CONCRETE MIX DESIGN FOR M 35 GRADE WITH FLY ASH

SPECIFICATIONS:

Slump Required = 75 mm

Degree of Control = Good

Exposure Condition = Severe

Type of Coarse Aggregate = Sub Angular

Zone of Aggregate = Zone - II

Size of Aggregate = 20mm

Fly Ash Content = 20%

Specific Gravity of Fine Aggregate = 2.65

Specific Gravity of Coarse Aggregate = 2.74

Specific Gravity of Cement = 3.15

Specific Gravity of Fly Ash = 2.2

1. Target Mean Strength:

From Table - 2 of IS 10262-2019

Standard Deviation for M35 grade concrete, S = 5 N/mm2

Target mean Strength, F'ck = 35 + (1.65*5) = 43.25 N/mm2

There fore, TARGET MEAN STRENGTH, F'ck = 43.25 N/mm2

2. Estimation of Air content:

From Table - 3 of IS 10262 - 2019

For 20mm aggregate, Entrapped Air = 1%

3. Water-Cement Ratio:

From Fig - 1 of IS 10262-2019,

Free water-cement Ratio = 0.39

From Table - 5 of IS 456-2000

For severe Exposure condition, Maximum W/C Ratio = 0.45

0.39 < 0.45. Hence, OK

Therefore, W/C Ratio = 0.39

4. Water Content:

From Table - 4 of IS 10262-2019,

For 20mm aggregate, Water content = 186 Litres or Kg

But For every increase in slump of 25mm we need to increase the water content by 3%

Water content= 1.03 x 186 = 191.58 Lit

Therefore, Water content = 191.58 Lit

5. Cement Content:

Cement Content = Water content/W/C Ratio

Cement Content = (191.58/0.39) = 491.23 kg

6. Cementitious and Fly Ash content:

As we are introducing the Fly ash, increase the cementitious content by 10%

Cementitious content = 1.10 x 491.23 = 540.35 kg

Water-Cementitous Ratio = (191.58/540.35) = 0.354

Therefore, Water/Cementitious Ratio = 0.354

Flyash content = 0.2 x 540.35 = 108.07 kg

Cement Content = 540.35 - 108.07 = 432.28 kg

7. Proportioning of volume of Coarse AggregaTe and Fine aggregate content:

From Table - 5, volume of coarse aggrege corresponding to 20mm size aggregae and Fine aggregate (Zone-II) for water-cement Ratio of 0.5 is 0.62

In present case, water-cementitious ratio is 0.354

Therefore, volume of coarse aggregate is required to be increased to decrease the fine aggregate content.

As the water-cement ratio is lower by 0.146, the proportion of volume of coarse aggregate is increased by 0.0292 (at the rate of increment of 0.01 for every decrease of 0.05 in water cement ratio and vice versa)

Therefore, Corrected proportion of Volume of Coarse aggregate = 0.6492

Volume of Fine aggregate = 1 - 0.6492 = 0.3508

8. Mix Calculations:

1. Total Volume = 1m3
2. Volume of Entrapped air in wet concrete = 0.01 m3
3. Volume of Cement = (Mass of cement/Specific Gravity of Cement) x (1/1000) = 0.137 m3
4. Volume of Fly Ash = (Mass of Fly Ash/Specific Gravity of Fly Ash) x (1/1000) = 0.049 m3
5. Volume of Water = (Mass of Water/Specific Gravity of Water) x (1/1000) = 0.192 m3
6. Volume of All in Aggregate = (a-(b+c+d+e)) = 0.612 m3
7. Mass of Coarse Aggregate = f x Volume of Coarse Aggregate x Specific Gravity of Coarse Aggregate = 1000 = 1088.63 kg
8. Mass of Fine Aggregate = f x Volume of Fine Aggregate x Specific Gravity of Fine Aggregate = 1000 = 568.927 kg

9. Mix Proportions:

1. Cement = 137 kg/m3
2. Fly Ash = 49 kg/m3
3. Water = 192 kg/m3
4. Fine Aggregate = 569 kg/m3
5. Coarse Aggregate = 1089 kg/m3
6. Free Water-Cementitious Materials Raio = 0.354

CONCRETE MIX DESIGN FOR M 50 GRADE WITHOUT FLY ASH

SPECIFICATIONS:

Slump Required = 75 mm

Degree of Control = Good

Exposure Condition = Severe

Type of Coarse Aggregate = Sub Angular

Zone of Aggregate = Zone - II

Size of Aggregate = 20mm

Specific Gravity of Fine Aggregate = 2.65

Specific Gravity of Coarse Aggregate = 2.74

Specific Gravity of Cement = 3.15

1. Target Mean Strength:

From Table - 2 of IS 10262-2019

Standard Deviation for M50 grade concrete, S = 5 N/mm2

Target mean Strength, F'ck = 50 + (1.65*5) = 58.25 N/mm2

There fore, TARGET MEAN STRENGTH, F'ck = 58.25 N/mm2

2. Estimation of Air content:

From Table - 3 of IS 10262 - 2019

For 20mm aggregate, Entrapped Air = 1%

3. Water-Cement Ratio:

From Fig - 1 of IS 10262-2019,

Free water-cement Ratio = 0.35

From Table - 5 of IS 456-2000

For severe Exposure condition, Maximum W/C Ratio = 0.45

0.35 < 0.45. Hence, OK

Therefore, W/C Ratio = 0.35

4. Water Content:

From Table - 4 of IS 10262-2019,

For 20mm aggregate, Water content = 186 Litres or Kg

But For every increase in slump of 25mm we need to increase the water content by 3%

Water content= 1.03 x 186 = 191.58 Lit

Therefore, Water content = 191.58 Lit

5. Cement Content:

Cement Content = Water content/W/C Ratio

Cement Content = (191.58/0.35) = 547.37 kg

6. Proportioning of volume of Coarse AggregaTe and Fine aggregate content:

From Table - 5, volume of coarse aggrege corresponding to 20mm size aggregae and Fine aggregate (Zone-II) for water-cement Ratio of 0.5 is 0.62

In present case, water-cementitious ratio is 0.35

Therefore, volume of coarse aggregate is required to be increased to decrease the fine aggregate content.

As the water-cement ratio is lower by 0.15, the proportion of volume of coarse aggregate is increased by 0.03 (at the rate of increment of 0.01 for every decrease of 0.05 in water cement ratio and vice versa)

Therefore, Corrected proportion of Volume of Coarse aggregate = 0.65

Volume of Fine aggregate = 1 - 0.65 = 0.35

7. Mix Calculations:

1. Total Volume = 1m3
2. Volume of Entrapped air in wet concrete = 0.01 m3
3. Volume of Cement = (Mass of cement/Specific Gravity of Cement) x (1/1000) = 0.1735 m3
4. Volume of Water = (Mass of Water/Specific Gravity of Water) x (1/1000) = 0.192 m3
5. Volume of All in Aggregate = (a-(b+c+d)) = 0.624 m3
6. Mass of Coarse Aggregate = f x Volume of Coarse Aggregate x Specific Gravity of Coarse Aggregate = 1000 = 1111.34 kg
7. Mass of Fine Aggregate = f x Volume of Fine Aggregate x Specific Gravity of Fine Aggregate = 1000 = 578.76 kg

8. Mix Proportions:

1. Cement = 174 kg/m3
2. Water = 192 kg/m3
3. Fine Aggregate = 579 kg/m3
4. Coarse Aggregate = 1112 kg/m3
5. Free Water-Cementitious Materials Raio = 0.35