Challenge

Project on Concrete Mix Design for various grades of Concrete

PPankaj Mohite19 Feb 2023

1. Calculate the Concrete Mix Design for M35 grade concrete with fly ash.

Ans:

1. Target Mean Strength= fck + 1.65s

= 35+ 1.65X5

= 43.25N/mm2

2. Water-Cement Ratio:

For extreme weather= 0.4

3. Water content for 20mm Aggregate= 186 Litre.

4. Cement content:

Cement = 186/0.4 = 465kg/m3

Fly Ash = 30% of cement= 465X 0.30= 139.5 kg/m3

Cement After= 70% = 325.5kg/m3

5. Aggregate volume:

for zone3= 0.64

Volume of course Aggregate: 0.64*0.9= 0.58

Volume of fine Aggr: 1-0.58= 0.42

6. Total Calculations:

a. 1m3

b. Volume of Cement: wgt. of cement/spe. gravity of cement X1/1000

= 326/3.15X1/1000= 0.103

c. Volume of Water: wgt. of Water/spe. gravity of Water X1/1000

= 186/1X1/1000

= 0.186

d. Volume of Admixture:

2% Of Cemtetious material: 9.3kg/m3

Volume of Adm: wgt. of Adm/spe. gravity of Adm X1/1000

= 9.3/ 1.145 X 1/1000

= 0.008

e= a-(b+c+d)

e= 1-(0.103+0.186+0.008)

e= 0.703

Volume of Course aggregate: eX Volume of Course AggregateX Spe. GravityX 1000

= 0.703X 0.58X2.74X1000= 1117kg

Volume of Fine aggregate: eX Volume of Fine AggregateX Spe. GravityX 1000

= 0.703X 0.42X2.74X1000= 809kg

Total Qty:

Cement: 326kg/m3

Water/Cement Ratio= 0.4

Admixture: 9.3kg/M3

Course Aggregate: 1117kg/m3

Fine Aggregate: 809kg/m3

Mix Proportion: 1: 2.48: 3.42

2. M50 grade concrete without Fly ash.

Ans:

1. Target Mean Strength= fck + 1.65s

= 50+ 1.65X5

= 58.25N/mm2