Concrete Mix Design

 Mix Design of Concrete (M-35) : 

1.       Characteristic Strength =35 N/mm²

2.       Target mean strength at 28 days as per Morth ,table 1700-3A =47 N/mm²

3.       Maximum Size of aggregate =20mm

4.       Type of Expose-Normal

5.       Degree of Quality Control-Good

6.       Minimum Cement content as per Morth,Table 1700-3A =400 kg/mm³

7.       Maximum water cement ratio as per morth,table 1700-3A---=0.45

8.       Air entrapped as per IS: 10262………=2.0%

9.       Grade of concrete-M35

10.   Workability required in terms of slump at site as per Morth, Table 1700-3 = 150 to 200 mm

11.   Cement Used Dalmia konarak OPC 53 Grade (IS: 12269-2013)

Coarse Aggregate:

As we will use Coarse Aggregate 20mm & 10mm (Normal Size), So we can have to satisfy 

combined grading criteria IS :383,Table -2. The proportions of Coarse aggregate and Fine 

aggregate are CA : FA=60:40 & CA1 (20mm) : CA2 (10mm) =50:50

20mm (Pakur Varity) Specific Gravity= 2.87

10mm (Pakur Varity) Specific Gravity= 2.83

       Specific Gravity  of Fine Aggregate=2.72

       Specific Gravity  of  Cement=3.15

       Water=1

CA:FA=60:40,CA1:CA2=50:50

W/C Ratio= 0.42

Cement =450 kg/m³

Water=450 x 0.42=189 kg/m³

For slump 175mm water content increased upto 15 %=189+15% of 189=217.35 lt/m³

Super Plasticizer (Admixture)  @ 0.8% was taken by weight of cement=450 x 0.8%=3.6 kg/m³

As super Plasticizer used the water content can be reduced  10%

Now water content is = 217.35 x 0.9=195.615 Lt

Now, Volume of Cement =450/3.15 x 1/1000 =0.142 m³

(Where, Weight of Cement=-450kg,Specific Gravity of  cement =3.15 )

Volume of water =195.615/1 X  1/1000 = 0.195 m³

Volume of Super Plasticizer = 3.6/1.11 X 1/1000 =0.003 m³

(Where, Weight of Super Plasticizer=3.6kg, specific gravity of S.P.=1.11 )

Volume of air Entrapped @ 2% =0.02 m³

Total Volume=(0.142+0.195+0.003+0.02)=0.360 m³

Volume of all in aggregate =(1 – 0.360)=0.64 m³

Mass of CA =0.64 x 2.85 x 0.60 x 1000=1094.40 Kg

 (Where, Vol of all in aggregate =0.64,Specific gravity of CA =2.85, CA : FA = 60: 40)

Mass of FA = 0.64 x 2.72 x 0.40 x 1000 = 696.32 kg

(Where, Vol of all in aggregate =0.64,Specific gravity of FA =2.72, CA : FA = 60: 40)

Now,

Cu.m  Before Moisture Correction,

Cement= 450kg

20 mm Aggregate= 547.20 kg

10 mm Aggregate= 547.20 kg

Fine aggregate= 696.32 kg

Water = 195.615 kg

Super plasticizer = 3.6 kg