Project on Concrete Mix Design for various grades of Concrete

Aim:

The aim is to design a Concrete Mix Design for M35-grade concrete with fly ash & M50-grade concrete without Fly ash.

Introduction:

This project will do the detailed design procedure and the design mix proportion of M35 and M50 grades of concrete, with the help of Is456-2000 and Is10262-2009 codes.

M35 Grade concrete with Fly ash:

1. Grade = M35
2. Type of cement = OPC 53
3. Max aggregate size = 20mm
4. Cement contetnt= Severe Exposure(320kg/mm3)
5. W/C ratio= from table -5 Is 456=0.45
6. Workability=120mm
7. Method of concrete Placing= Pumping
8. Supervision= Good
9. Type of aggregate= Crushed Angular Aggregate
10. Cement content= As per IS456-2000
11. Chemical admixture= Superplasticizer

Material Properties:

1. Cement used= OPC 43 garde
2. Specific Gravity of cement=3.15
3. Fly Ash
4. SG of Fly ash=2.2
5. Chemical admixture= Superplasticizer
6. Sg of CA=02.74, FA=2.65 and CHAD=1.145
7. Water Absorption= CA=0.5% & FA=1.0%
8. Surface Moisture for the CA and FA are 2% and 5%
9. CA Moisture = 2-0.5= 1.5%
10. FA Moisture= 5-1=4%

Calculation:

1. Target Mean Srength=ft=fck+1.65*s= 35+1.65*5 = 43.25N/mm2
2. Selection of water/cement ratio, desired w/c ratio is 0.37<0.45 hence ok
3. Selection of water content from table 4 IS 10262-2009, water content for 20mm agg is 186 lit. ( For The water content for 120mm slump the rate is will be increasing by 3% for every 25mm slump)
4. 186+8.4/100*186 = 201.62kg
5. Based on the trail data, the water content is reduced by 23%, hence the arrived water content = 201.62*0.77= 155kg
6. calculation of cement content w/c=0.37
7. cement content=155/0.37 = 419kg/m3
8. From is IS456-2000, for severe condition the value is 320kg/m3 the value we got is 419kg/m3 hence ok.
9. Lets increase 10% of cement content = 419*1.1= 460kg/m3
10. water content =155kg
11. so the ratio = 155/460=0.336
12. Let us 30% of fly ash=460*0.3=138kg/m3
13. Cement =460-138=322kg/m3

volume of aggregate calculation:

1. From table 5 Is10262-2009, Let's take zone II and w/c ratio 0.5=0.62
2. At the w/c ratio is lower by 0.17 the proportion is increased to 0.034
3. The volume of coarse aggregates for water/cement ratio=0.62+0.034=0.654
4. For the pumped concrete the value was reduced by 10% i.e 0.654*0.9=0.59m3

Mix Calculation:

1. Volume of Concrete=1m3
2. volume of entrapped air in wet concrete= 0.01m3
3. Volume of cement= Mass of cement/SG of cement*0.001 =322/3.15*0.001=0.102m3
4. Volume of Fly ash=Mass of Fly ash/SG of Fly ash*0.001 =138/2.2*0.001 = 0.068m3
5. Volume of water=Mass of water/SG of water*0.001 = 1.55/1*0.001 = 0.15m3
6. Volume of chemical admixture(1%) = Mass of chemical adm/SG of chemical adm*0.001 = 1% of 460 = 4.6 = 4.6/1.145*0.001 = 0.0040m3
7. Volume of all aggregate (a-b)-(c+d+e+f) = (1-0.01)-(0.102+0.0828+0.155+0.040) = 0.666m3
8. Mass of CA= Vol. of all agg * Vol of CA*SG of CA*1000 = 0.666*0.59*2.74*10 = 1077kg
9. Mass of FA= Vol. of all agg * Vol of FA*SG of FA*1000 = 0.666*0.41*2.65*1000 = 724kg

Mix Proportion

1. Cement = 322kg/m3
2. Fly ash = 138kg/m3
3. Water = 155kg/m3
4. FA = 724kg/m3
5. CA = 1077kg/m3
6. Chemical admixture = 4.6kg/m3
7. Free water/cement ratio = 0.336

Mix Design For M50 grade concrete without Fly ash

1. Grade = M50
2. Type of cement = PPC
3. Max aggregate size = 20mm
4. Cement content= Severe Exposure(320kg/mm3)
5. W/C ratio= from table -5 Is 456=0.45
6. Workability=75mm
7. Method of concrete Placing= Pumping
8. Supervision= Good
9. Type of aggregate= Crushed Angular Aggregate
10. Cement content= As per IS456-2000
11. Chemical admixture= Superplasticizer

Material Properties:

1. Cement used= PPC
2. Specific Gravity of cement=2.88
3. SG of Fly ash=2.2
4. Chemical admixture= Superplasticizer
5. Sg of CA=02.74, FA=2.65 and CHAD=1.145
6. Water Absorption= CA=0.5% & FA=1.0%
7. Surface Moisture for the CA and FA are 2% and 5%
8. CA Moisture = 2-0.5= 1.5%
9. FA Moisture= 5-1=4%

Calculation:

1. Target Mean Srength=ft=fck+1.65*s= 50+1.65*5 = 58.25N/mm2
2. Selection of water/cement ratio, desired w/c ratio is 0.28<0.45 hence ok
3. Selection of water content from table 4 IS 10262-2009, water content for 20mm agg is 186 lit. ( For The water content for 75mm slump the rate is will be increasing by 3% for every 25mm slump)
4. 186+3/100*186 = 191.58kg
5. Based on the trail data, the water content is reduced by 23%, hence the arrived water content = 191.58*0.77= 147.5kg
6. calculation of cement content w/c=0.28
7. cement content=148/0.28 = 529kg/m3

volume of aggregate calculation:

1. From table 5 Is10262-2009, Let's take zone II and w/c ratio 0.5=0.62
2. At the w/c ratio is lower by 0.17 the proportion is increased to 0.044
3. The volume of coarse aggregates for water/cement ratio=0.62+0.044=0.664
4. For the pumped concrete the value was reduced by 10% i.e 0.664*0.9=0.59m3

Mix Calculation:

1. Volume of Concrete=1m3
2. volume of entrapped air in wet concrete= 0.01m3
3. Volume of cement= Mass of cement/SG of cement*0.001 =529/2.88*0.001=0.18m3
4. Volume of water=Mass of water/SG of water*0.001 = 148/1*0.001 = 0.148m3
5. Volume of chemical admixture(1%) = Mass of chemical adm/SG of chemical adm*0.001 = 1% of 529 = 5.29 = 5.29/1.145*0.001 = 0.0046m3
6. Volume of all aggregate (a-b)-(c+d+e) = (1-0.01)-(0.18+0.148+0.0046) = 0.6574m3
7. Mass of CA= Vol. of all agg * Vol of CA*SG of CA*1000 = 0.6574*0.664*2.74*1000 = 1196kg
8. Mass of FA= Vol. of all agg * Vol of FA*SG of FA*1000 = 0.657*0.336*2.65*1000 = 585kg

Mix Proportion

1. Cement = 529kg/m3
2. Water = 148kg/m3
3. FA = 585kg/m3
4. CA = 1196kg/m3
5. Chemical admixture = 5.29kg/m3
6. Free water/cement ratio = 0.28