Project on Concrete Mix Design for various grades of Concrete
1.MIX DESIGN FO M35 GRADE CONCRETE WITH FLYASH
STIPULATIONS FOR PROPORTIONING
Grade designation : M35
Type of cement : opc 33 Grade
Type of mineral Admixture : Flyash
Maximum nominal size of aggregate : 20mm
Maximum water cement ratio : 0.45
Workability : 100mm Slump
Exposure condition : Severe
Method of Placing : Pumping
Chemical Admixture : Super Plasticizer
Test Data
Specific Gravity of cement : 3.15
Specific Gravity of CA : 2.75
Specific Gravity of FA : 2.75
Specific Gravity of Flyash : 2.20
Specific Gravity of Chemical Admixture : 1.15
Seive Analysis : Zone I
Target Strength
= Fck+1.65s
S= standard deviation
S for M35 grade concrete is 5
= 35+(1.65*5)
= 43.5 N/mm2
Selection Of Water Cement Ratio
Free Water cement ratio for OPC 33 grade concrete from curve is 0.35
It is less than Maximum water cement Ratio 0.35<0.45
Hence OK
Water Content
From Table 7, for 20mm coarse aggregate
W= 186 Lit (for 25 to 50mm Slump)
For 100mm Slump = 186+(0.006*186)
W = 197 lit
Because of using Superplasticizers water content may be reduced by 29%
W = 197*0.71
= 140 lit
Cement and Flyash Content
W/C = 0.35
140/C = 0.35
C= 140/0.35
C = 400 kg/m3
From Table 5 in Is 456:2000 Minimum cement Content in Severe Condition is 320kg/m3
Hence Ok
Cementitious content is increased by 10% for using Flyash
= 400*1.10
= 440 kg/m3
Water Content =140 lit
water Cementitious ratio = 140/440
= 0.318 say 0.32
using Flyash as 30% of Cementitious content
= 0.3*440
= 132 kg/m33
OPC = 440-132
= 308 kg/m3
Proportion of Volume of Coarse Aggregate and Fine Aggregate
For Zone I If the water cement ratio is 0.50 then CA is 0.60 ( for water cement ratio is +-0.05 then the ratio is +-0.01)
w/c =0.32,
CA = 0.636
For Pumpable concrete CA is reduced by 10%
CA = 0.9*0.636
= 0.572
FA = 1-0.572
= 0.428
Mix Calculations
(a) Volume of Concrete = 1 m3
(b) Volume of cement = Mass of Cement/(Specific gravity of cement x 1000)
= 308/(3.15*1000)
= 0.097 m3
(c) Volume of Flyash = Mass of Flyash/(Specific gravity of Flyash x 1000)
= 132/(2.2*1000)
= 0.059 m3
(d) Volume of Water = Mass of Water/(Specific gravity of Water x 1000)
= 140/(1*1000)
= 0.14 m3
(e) Volume of Superplasticizers = Mass of Superplasticizers/(Specific gravity of SuperPlasticizers x 1000)
(2% of Cementitious material) = 8.8/(1.15*1000)
= 0.007 m3
(f) Volume of Aggregates = a-(b+c+d+e)
= 1-(0.097+0.059+0.140+0.007)
=1- 0.303
= 0.697 m3
Mass of coarse Aggregate = 0.697*0.572*2.75*1000
= 1096 kg
Mass of Fine Aggregate = 0.697*0.428*2.75*1000
= 820 kg
MIX PROPORTIONS
CEMENT = 308 Kg/m3
FLYASH = 132 Kg/m3
WATER = 140 Kg/m3
FINE AGGREGATE = 820 kg/m3
COARSE AGGREGATE = 1096 kg/m3
CHEMICAL ADMIXTURE = 8.8 Kg/m3
WATER CEMENT RATIO = 0.32
MIX RATIO = 1 : 2.66 : 3.55
2.MIX DESIGN FO M50 GRADE CONCRETE
STIPULATIONS FOR PROPORTIONING
Grade designation : M50
Type of cement : Opc 53 Grade
Maximum nominal size of aggregate : 20mm
Maximum water cement ratio : 0.45
Workability : 100mm Slump
Exposure condition : severe
Method of Placing : Pumping
Chemical Admixture : Super Plasticizer
Test Data
Specific Gravity of cement : 3.15
Specific Gravity of CA : 2.75
Specific Gravity of FA : 2.75
Specific Gravity of Chemical Admixture : 1.15
Seive Analysis : Zone I
Target Strength
= Fck+1.65s
S= standard deviation
S for M50 grade concrete is 5
= 50+(1.65*5)
= 58.25 N/mm2
Selection Of Water Cement Ratio
Free Water cement ratio for OPC 53 grade concrete from curve is 0.35
It is less than Maximum water cement Ratio 0.33<0.45
Hence OK
Water Content
From Table 7, for 20mm coarse aggregate
W= 186 Lit (for 25 to 50mm Slump)
For 100mm Slump = 186+(0.006*186)
W = 197 lit
Because of using Superplasticizers water content may be reduced by 29%
W = 197*0.71
= 140 lit
Cement Content
W/C = 0.33
140/C = 0.33
C= 140/0.33
C = 424 kg/m3
From Table 5 in Is 456:2000 Minimum cement Content in Severe Condition is 320kg/m3
Hence Ok
Proportion of Volume of Coarse Aggregate and Fine Aggregate
For Zone I If the water cement ratio is 0.50 then CA is 0.60 ( for water cement ratio is +-0.05 then the ratio is +-0.01)
w/c =0.33,
CA = 0.634
For Pumpable concrete CA is reduced by 10%
CA = 0.9*0.634
= 0.57
FA = 1-0.57
= 0.43
Mix Calculations
(a) Volume of Concrete = 1 m3
(b) Volume of cement = Mass of Cement/(Specific gravity of cement x 1000)
= 424/(3.15*1000)
= 0.134 m3
(c) Volume of Water = Mass of Water/(Specific gravity of Water x 1000)
= 140/(1*1000)
= 0.14 m3
(d) Volume of Superplasticizers = Mass of Superplasticizers/(Specific gravity of SuperPlasticizers x 1000)
(2% of Cementitious material) = 8.48/(1.15*1000)
= 0.007 m3
(e) Volume of Aggregates = a-(b+c+d)
= 1-(0.134+0.140+0.007)
=1- 0.281
= 0.719 m3
Mass of coarse Aggregate = 0.719*0.57*2.75*1000
= 1127 kg
Mass of Fine Aggregate = 0.719*0.43*2.75*1000
= 850 kg
MIX PROPORTIONS
CEMENT = 424 Kg/m3
WATER = 140 Kg/m3
FINE AGGREGATE = 850 kg/m3
COARSE AGGREGATE = 1127 kg/m3
CHEMICAL ADMIXTURE = 8.48 Kg/m3
WATER CEMENT RATIO = 0.33
MIX RATIO = 1 : 2 : 2.65